Brain & Cognition Flashcards
(284 cards)
1
Q
describe single unit recording.
A
Electrodes, consisting of thin wire strands, are implanted into specific areas of the brain. Recordings of this brain cell activity are made by measuring the electrical potential of nearby neurons that are in close proximity to the electrode.
too invasive for humnas.
2
Q
Describe EEG.
A
Electroencephalography (EEG) is the measurement of the electrical activity of the
brain by recording from electrodes placed on the scalp. The resulting traces are
known as an electroencephalogram (EEG) and represent an electrical signal from a
large number of neurons.
non invasive.
The conversion of the raw EEG from three electrodes (F3, C3 and P3) into the
four classical EEG frequencies: from slowest to fastest (delta, theta, alpha and
beta).
EEG signals represent the temporal profile of the change in the
potential difference between two electrodes placed on the scalp.
3
Q
what are ERPs?
A
When populations of neurons are active in synchrony, they produce an electric field that
can be detected at the scalp (EEG). When many waves are averaged and linked to the
onset of the stimulus, then an ERP is obtained
The EEG obtained on several trials can be averaged together
time locked to the stimulus to form an event-related potential (ERP).
ERPs are voltage fluctuations that are associated in time with particular event (visual, auditory, olfactory stimuli) ERPs can be recorded from the human scalp and extracted from the ongoing electroencephalogram EEG by means of filtering and signal averaging.
4
Q
How can ERP’s be used?
A
to study facial recognition.
Different ERP peaks associated with different aspects of face processing.
• The N170 is relatively specialized for faces,
recorded from rPSTS sites
• The P300 – famous and familiar faces.
A comparison between the ERPs from patients with Alzheimer’s disease
and those from control subjects. A markedly reduced P300 is seen for the
demented patients at each electrode site
5
Q
describe MEG.
A
Magnetoencephalography (MEG) is an imaging technique used to measure
the magnetic fields produced by electrical activity in the brain via extremely
sensitive devices known as SQUIDs. These measurements are commonly
used in both research and clinical settings. Excellent temporal and spatial
resolution.
non invasive
6
Q
Describe MRI
A
Uses differential magnetic properties of types of tissue and of
blood to produce images of the brain.
7
Q
Describe structural MRI scanning
A
- Detection of brain damage
- Detection of lesion (brain damage) location
- Measurement of lesion extent
- Detection of damage to connections
different types of tissue (skull, gray matter, white matter, CSF
fluid) have different physical properties – used to create STATIC maps (CT
and structural MRI)
8
Q
Describe functional imaging.
A
temporary changes in brain physiology associated with cognitive processing (PET & fMRI)
9
Q
describe CT scans
A
Computed tomography (CT) scanning
builds up a picture of the brain based on
the differential absorption of X-rays.
CT scans reveal the gross features of the brain but do not resolve its structure well.
10
Q
Describe PET
A
Functional imaging.
Positron Emission Tomography (PET) uses trace amounts of short-lived
radioactive material to map functional processes in the brain. When the
material undergoes radioactive decay a positron is emitted, which can be
picked up be the detector. Areas of high radioactivity are associated with
brain activity.
11
Q
describe fMRI
A
functional MRI
Neuronal activity requires oxygen and glucose (energy)
• Neuronal activity produces changes in blood oxygenation levels
• fMRI uses the contrast between oxygenated and deoxygenated
blood
• They have different magnetic properties and so fMRI can provide
information about brain activity.
fMRI can be used to produce activation maps showing which parts of the brain are involved in a particular mental process.
12
Q
describe the BOLD response.
A
blood oxygenation dependent level.
blood flow increases when stimulus is applied.
looks like an action potential.
13
Q
describe DTI
A
diffusion tensor imaging.
An imaging method that uses a modified MRI scanner to reveal bundles of
axons in the living brain
We can visualize connections in the brain.
muse 2nd law.
14
Q
What is TMS?
A
transcranial magnetic stimulation.
a means of disrupting normal brain activity by introducing
neural noise – ‘virtual lesion’
Michael Faraday.
Faraday’s coil. magnetic field must be changing - ie switching on and off.
Apply TMS pulse at any cortical node of the network, TMS
will interfere with the reading relevant neural signal:
– efficacy of that signal will be degraded
– behavioural decrement (RT change – it will take us
longer to read).
Advantages of TMS: • Interference/virtual lesion technique. • transient and reversible • Control location of stimulation • Establishes a causal link of different brain areas and a behavioural task
15
Q
best approach to explore brain function?
A
convergent approach, use various methods at once.
16
Q
What does Anterior Posterior Dorsal Ventral Lateral Medial Ipsilateral Contralateral Caudal mean?
A
Anterior Front Posterior Back Dorsal Top Ventral Bottom Lateral Toward side Medial Toward Middle Ipsilateral Same side Contralateral Opposite side Caudal Tail
17
Q
What is the transverse section?
A
right angle to the neuraxis.
18
Q
What is the sagittal section?
A
parallel to neuraxis and perpendicular to the ground.
19
Q
What is the horizontal section?
A
parallel to the ground.
20
Q
what is in the CNS?
A
brain and spinal cord.
21
Q
what is in the PNS?
A
cranial nerves and spinal nerves.
22
Q
what allows the passage of the spinal cord?
A
the foramen magnum
dont need to know
23
Q
What is the dura mater?
A
the outermost layer of the meninges.
tough and flexible.
24
Q
What is the arachnoid?
A
middle layer of the meninges.
does not dip into the valleys of the brain contour.
25
What is the pia mater?
last layer of the meninges, adheres to the surface of the brain.
space between arachnoid and pia is filled with Cerebral spinal fluid.
26
what are ventricles?
a set of hollow chambers filled with CSF. Where it is produced.
2 lateral ventricles
third ventricle
cerebral aqueduct (connects 3 and 4)
fourth ventricle
27
describe CSF.
Similar to blood plasma composition
• Formed by the choroid plexus
• Forms a watery cushion to protect the brain
• Circulated in arachnoid space, ventricles, and central canal of the
spinal cord
• Total volume of cerebrospinal fluid = 125-150 ml
• The entire volume of cerebrospinal fluid turns over 3 to 4 times
per day
• CSF is actively secreted by the brain. CSF is constantly being
made, circulates and is reabsorbed into the blood stream
28
What produces CSF?
choroid plexus.
| Most created in 3rd ventricle, some in 4th.
29
what is hydrocephalus?
"water head"
can be due to mother having measels or rubella.
one ventricle gets blocked, usually 3rd.
ventricles get bigger due to excess fluid.
Head gets bigger, skull is still flexible as a baby.
insert a valve to drain to abdominal cavity at the correct pace.
30
Describe telencephalon.
contains the cerebral cortex, basal ganglia and the limbic system.
located in the forebrain in the lateral ventricle.
31
describe diencephalon.
contains the thalamus and hypothalamus.
| located in the forebrain in the third ventricle.
32
describe mesencephalon.
contains the tectum tegmentum.
| located in the midbrain in the cerebral aqueduct.
33
describe metencephalon
contains the cerebellum and pons.
| located in the hindbrain in the fourth ventricle.
34
describe myelencephalon.
contains the medulla oblongata, loctaed in the hindbrain in the fourth ventricle.
35
describe the forebrain.
largest section of the brain, contains the telencephalon and diencephalon.
36
describe the cerebral cortex.
thin layer of tissue covering the brain consisting of two hemispheres.
37
what are the bumps and grooves on the brain?
gyrus - bump
| sulcus - groove.
38
what is grey matter?
composed of cell bodies of the neurones.
39
what is white matter?
axons and dendrites of the neurones, myelinated
40
how do the two hemisphers communicate?
through the corpus callosum.
41
how do you remember the location of the lobes?
FPOT.
frontal parietal occipital temportal
going clockwise around.
42
what is a fissure?
a very large deep groove.
43
where is the central fissure?
sylvian
occiptal
exoociptal??
central fissure between frontal and parietal lobe.
sylvian between temportal and frontal.
occiptal between parietal and occiptal
look up pic
44
what are the primary coritices?
involved in senses and motor functions.
45
where is the primary visual cortex?
in the occipital lobe at the back of the head.
46
where is the auditory cortex?
superior temporal gyrus.
47
superior, medial, inferior?
when locating something, how high up???
48
what seperates the primary motor cortex and the primary somatosensory cortex?
central sulcus
49
what does the primary motor cortex do?
Neurons in different regions of the motor cortex connect to muscles in different regions of the contralateral side of the body
50
what does the primary somatosensory cortex do?
It receives information from the body senses; different regions receive information from different parts of the body.
51
what is a brodmann area?
a region of the cerebral cortex based on it's structure n shit.
52
what is the limbic system?
set of structures involved in learning, memory, and emotion.
telencephalon
```
contains:
Limbic Cortex
Hippocampus
Amygdala
Fornix
Mammillary Bodies (part of the hypothalamus)
```
53
describe the basal ganglia.
telencephalon.
set of structures involved in processing information for motor movement. Major structures of the basal ganglia motor system include:
•Caudate Nucleus
•Putamen
•Globus Pallidus
54
What does the Thalamus do?
diencephalon. forebrain
Main sensory relay for all senses (except smell) and the cortex.
Lateral GN and Medial Geniculate Nucleus
55
What does the hypothalamus do?
diencephalon. forebrain
| set of nuclei involved in regulating the autonomic nervous system, controlling the pituitary gland.
56
describe the midbrain.
mesencephalon - comprised of the tectum and tegmentum.
tectum - roof
tegmentum - covering
57
describe the tectum.
mesencephalon.
```
contains:
1. superior colliculi – subcortical
sensory pathway involved in fast eye
movements (vision)
2. inferior colliculi - part of auditory
pathway
```
58
Describe the tegmentum
mesencephalon.
role in motor movement
1. reticular formation (sleep and wake cycles)
2. red nucleus (movement)
3. substantia nigra (movement) can lead to parkinsons if damaged.
59
describe the hindbrain.
Contains both the metencephalon and the myelencephalon.
60
describe the cerebellum.
• appears as a mini brain
• involved in motor coordination and
smooth execution of movement
61
describe the pons.
* part of the reticular formation
* involved in sleep and arousal
* link between cerebllum and cerebrum
62
describe the medulla oblongata.
myelencephalon.
involved in basic life functions, such as breathing, swallowing, heart rate and wake-sleep cycles.
63
describe the spinal cord.
CNS tissue extending caudally
from the medulla in the brain
The spinal cord communicates with
the sense organs and muscles
below the level of the head
Primary Components of the Spinal
Cord:
• Dorsal Roots
• Ventral Roots
white matter on the surface, grey matter on the inside.
64
how is matter arranged in the brain?
white matter in the centre, grey matter on the surface.
65
describe dorsal roots.
afferent, carry sensory info to the CNS
66
describe ventral roots.
carry motor info to the muscles and glands, efferent.
| away from the CNS
67
describe the peripheral nervous system.
Located outside of the skull and spine.
It comprises of two parts: the somatic and the autonomic nervous systems.
Brings information into the CNS and carry signals out of the CNS.
68
somatic nervous system?
The part of the peripheral nervous system that controls the
movement of skeletal muscles or transmits somatosensory
information to the central nervous system
69
autonomic nervous system?
The portion of the peripheral nervous system that controls the body’s vegetative functions.
70
describe cranial nerves.
12 motor/sensory nerves attached to the ventral surface of the brain.
efferent motor, afferent sensory.
71
describe spinal nerves.
peripheral nerves attached to the spinal cord.
31 pairs
afferent and efferent travel to muscles and sensory receptors.
72
autonomic nervous system?
all nerves are efferent.
Regulation of smooth muscles, cardiac muscle and glands.
Comprised of the sympathetic and parasympathetic divisions.
Sympathetic and parasympathetic nerves generally have opposite effects.
Sympathetic
“Fight or flight”
Arousal and preparing the body
for the expenditure of energy
Parasympathetic
“Rest and restore”
Relaxing the body
73
what is the cell body?
soma
74
describe the types of neurones.
Sensory neurons- detect changes in external and internal environment (CNS and
PNS, light, sound, odours, touch...).
Motor neurons- controls muscle contraction and also gland secretion (CNS and
PNS).
Interneurons- lie entirely within the CNS and are involved in cognition
(i. e.,perceiving, learning, remembering and executive functioning such as decision
making) .
75
describe multipolar neurons
neuron with one axon and many dendrites attached to its soma.
76
describe bipolar neurons
neuron with one axon and one dendrite attached it its soma.
77
dsecribe unipolar neurons
neuron with one axon attached to its soma; the axon divides, with one branch receiving sensory information and the other sending the information into the central nervous. system.
78
what forms myelin sheaths?
oligodendrocytes. CNS
| schwann cells PNS
79
what do astrocytes do?
form support for CNS.
help form the blood brain barrier.
secrete neurotrophic factors.
take up K+ NT.
```
• “Star cells”
• Provide physical support to
neurons
• Provide nourishment
• When neurons die they clean up
debris and form scar tissue
• Control chemical composition of
fluid surrounding neurons
```
80
what do microglia do?
modified immune cells
| act as scavengers?
81
what do ependymal cells do?
create barriers between compartments.
| source of neural stem cells.
82
what is the blood brain barrier?
A semipermeable barrier between the CNS and circulatory system, which helps to regulate the flow of nutrient rich fluid into the brain.
83
what is the area postrema?
a region of the medulla where the blood-brain barrier is weak. This allows toxins in the blood to stimulate this area,
which initiates vomiting – poison expelled from the body.
84
what is the membrane potential?
electrical charge across a cell
membrane; the difference in
electrical potential inside and
outside the cell.
85
resting potential?
membrane potential of a neuron when it is not being altered by excitatory or inhibitory postsynaptic potentials, normally about -70 mV.
86
depolarization?
reduction (toward zero) of the membrane potential when we stimulate neuron
87
action potential yo
ye
88
describe electrostatic pressure.
when substances dissolve in water, they
split into 2 parts with opposing electrical charge Na + and Cl− : IONS.
```
Attraction of oppositely charged ions (+-) and repulsion of similarly
charged ions (++; - -) is exerted by electrostatic pressure
```
89
what is the Direct opening of ion channel?
an ionotropic receptor.
90
what is the indirect opening of an ion channel?
metabotropic receptor.
91
what is an EPSP?
excitatory depolarization of the postsynaptic membrane.
Excitatory Postsynaptic Potential
92
what is an IPSP?
Inhibitory Postsynaptic Potential.
inhibitory hyperpolarization of
the post synaptic membrane.
93
describe Na K and Cl
Sodium (+) EPSP
Potassium (+) IPSP,
Chloride (-) IPSP
94
what effect does glutamate have?
excitatory
95
what effect does GABA and glycine have?
inhibitory
| also in the spinal cord
96
what is an antagonist?
A drug that opposes or inhibits the effects of a particular neurotransmitter on
the postsynaptic cell.
97
what is an agonist?
A drug that facilitates the effects of a particular neurotransmitter on the
postsynaptic cell.
98
what is an indirect agonist/antagonist?
```
A drug that attaches to a binding site
on a receptor and facilitates the action
of the receptor; does not interfere with
the binding site of the principal
neurotransmitter
```
99
what is a direct agonist/antagonist?
A drug that binds with and activates
(opens or blocks) a receptor. This drug
mimics the neurotransmitter
100
how can reuptake be prevented?
In the first case the drug attaches to the transporter molecules that are responsible
for reuptake and inactivate them - blocking reuptake.
In the second the drug bind with the enzyme that normally destroys the
neurotransmitter and prevents the enzymes from working.
Both types of drugs prolong the presence of the neurotransmitter in the synaptic
cleft (and hence in a location where they can stimulate postsynaptic receptors),
they serve as agonists.
101
describe acetylcholine
The primary neurotransmitter secreted by the efferent axons of the CNS.
All muscular movement is accomplished by the release of acetylcholine.
ACh is involved in regulating REM sleep - dreaming (doroslateral pons), perceptual
learning (basal forebrain), and memory (hippocampus).
ACh receptors: nicotinic and muscarinic
ACh found at the target of parasympathetic branch of the ANS – outside of the CNS,
first discovered neurotransmitter – the importance of Otto Loewi.
The effects of ACh are generally facilitatory
102
what is a nicotinic receptor?
an ionotropic acetylcholine receptor stimulated by nicotine
103
what is a muscarinic receptor?
a metabotropic acetylcholine receptor.
produces parasympathetic nerve effects in the heart, smooth muscles and glands.
GPCR
stimulated by muscarine
104
describe curare.
blocks nicotinic ACh receptors at synpases, causes paralysis.
105
describe atropine
Atropine prevents Ach from depolarising the postsynaptic membrane and so prevents generation of the impulse in this cell.
106
describe botulinum toxin
prevents ACh release by terminal buttons, "botox"
| antagonist
107
describe black widow spider venom
agonist, A poison produced by the black widow spider triggers the release of ACh.
108
what is a cholinergic synapse?
Synapses that have acetylcholine
transmitter are called cholinergic
synapses.
109
describe the action of a cholinergic synapse.
An action potential arrives at
presynaptic membrane. Voltage gated calcium channels in the presynaptic membrane open, calcium ions enter the presynaptic neuron.
Calcium ions cause synaptic vesicles to fuse with the presynaptic membrane, releasing acetylcholine into the synaptic cleft.
Acetylcholine diffuses cross the synaptic cleft and binds to specific neuroreceptor sites in the post synaptic membrane.
Sodium channels open. Sodium ions diffuse into the postsynaptic membrane causing depolarisation, which may initiate an action potential.
Acetylcholinesterase (enzyme) breaks down acetylcholine.
The products diffuse back into the presynaptic neuron where acetycholine is resynthesised using ATP from the mitochondria.
110
describe a neuromuscular junction.
```
Same stages as cholinergic synapses,
but in this case the postsynaptic
membrane is the muscle fibre membrane
(Sarcolemma).
Depolarisation of the sarcolemma leads
to contraction of muscle fibre.
```
111
what is a tolerance?
• A state in which organism no
longer responds to a drug
• A higher dose is required to
achieve the same effect
112
what is dependence?
A state in which organism functions normally only in the presence of a drug
Manifested as physical disturbance when the drug is withdrawn
113
what is the nigrostriatal system?
starts in the substantia nigra and terminates in the basal ganglia : plays a role in the control of movement.
degeneration leads to parkinsons
114
how is dopamine treated?
L-DOPA, dopamine precursor.
115
what is the mesolimbic system?
Starts in the ventral tegmental area and terminates in the nucleus accumbens, amygdala, and hippocampus; plays a role
in the reinforcing effects of drugs that are commonly abused.
116
where is the reward system?
nucleus accumbens to the prefrontal cortex.
117
what is addiction?
a state in which an organism engages in compulsive behaviour,
behaviour is reinforcing (rewarding, pleasurable), loss of control for limiting intake
118
what does cocaine do?
increase reward system in caudate nucleus??
| higher glucose metabolism, not used as effectively.
119
describe serotonin.
also called 5-HT
play a role in the regulation of mood, the control of eating, sleeping, dreaming, and
arousal, temperature regulation, mood, cardiovascular function, muscle contraction,
endocrine regulation and depression.
involved in the regulation of pain.
The cell bodies of serotogenic neurons found in: midbrain, pons and medulla.
120
where is serotonin produced?
raphe nuclei in midbrain, pons and medulla
121
describe LSD.
LSD stimulates centers of the sympathetic nervous system in the midbrain, which
leads to pupillary dilation, increase in body temperature, and rise in the blood-sugar
level. LSD also has a serotonin-blocking effect.
serotonin antagonist
122
describe MDMA.
A drug that serves as a noradrenergic and
| serotonergic agonist, also known as “ecstasy”; has excitatory and hallucinogenic effects.
123
how does MDMA work.
1. Prevent reuptake.
2. Leaving more 5-HT in the synaptic
Cleft.
3. Bringing more 5-HT to the synaptic cleft.
124
describe depression and MDMA
Low serotonin levels are believed to be the cause of many cases of mild to severe
depression which can lead to symptoms such as anxiety, apathy, fear, feelings of
worthlessness, insomnia and fatigue.
If depression arises as a result of a serotonin deficiency then pharmaceutical agents
that increase the amount of serotonin in the brain should be helpful in treating
depressed patients. Anti-depressant medications increase serotonin levels at the
synapse by blocking the reuptake of serotonin into the presynaptic cell.
125
describe norepinephrine
Norepinephrine (NE) is both a hormone and a neurotransmitter. As a
hormone, secreted by the adrenal gland, it works alongside epinephrine /
adrenaline to give the body sudden energy in times of stress, known as the
"fight or flight" response.
Medications that inhibit the reuptake of NE can be effective to treat
depression. In addition, elevated NE are found in patients experiencing
mania
126
describe glutamate
An amino acid; the most important excitatory neurotransmitter in the brain.
127
describe NMDA receptors
A specialized ionotropic glutamate receptor
128
describe PCP
angel dust, synthetic drug – Indirect anatgonist of NMDA.
129
describe GABA
GABA is the most important inhibitory neurotransmitter in the brain and glycine in
the spinal cord.
Imbalances in GABA also are relevant to bipolar disorder, schizophrenia and
anxiety disorder.
The GABA neurotransmitter and its receptors are critical to how humans think
and act
GABA is part of the brain system that allows us to fine-tune our moods,
thoughts, and actions with an incredible level of detail
GABA - driving a car. You need the accelerator, but at every stage you need the
brakes to work. Some of our neurotransmitters apply the spark and the gas to the engine, and GABA supplies the brakes
GABA provides the necessary inhibitory effect that we need in order to block out
excessive brain activity that in depression may lead to excessive negative thinking
130
describe Benzodiazepine
indirect agonist of GABAA receptor, used for their tranquilizing effects: Valium (diazepam)
131
what are the stages of memory?
event/study
delay
recall/test
132
what is incidental encoding?
not telling somebody they are learning the words to be test on.
intentional is the converse.
133
what is primary memory?
william james.
| information that remains in consciousness after it has been perceived, forms part of the psychological present.
134
what is secondary memory?
william james.
information about events that have left
consciousness, part of the psychological past.
135
what did Hermann Ebbinghaus methods include?
‘CVC’ (consonant-vowel-consonant) nonsense syllables. ie VUL
Savings (less time to relearn once already learnt).
Effects of overlearning.
Stimulus-stimulus associations, despite being meaningless some associations would be made.
average capacity of short-term memory = 7 (+/-2)
recollection or familiarity.
136
what is the modal model of memory?
summary of all the models from the time (1960's).
sensory input --> sensory store.
if ignored it decays but if not goes to a short-term store.
with rehearsal --> long term store. if not displaced.
report from the short term store, by retrieving from the long term store.
short term
duration - 20s
capacity - 7 (+/-2)
code - phonological
137
what is the short vs long term store?
Free Recall Task:
– List of words (or syllables) presented at a fixed pace
– Subjects recall words in any order
– Recall plotted as a function of word’s position in list.
people are more likely to recall the first few words and the last few words. middle words are forgotten the most.
primacy effect - first few
recency effect - last few
U shaped curve indicates 2 processes/factors active. each highest at either end.
138
what is the recency effect?
last few items tend to be recalled.
139
how does a delay condition effect the recency effect?
longer delay decreases the recency effect.
| ie wait 30 seconds, can't recall last items.
140
what is the primacy effect?
first few items tend to be recalled.
141
how does rehearsal effect primacy effect?
rehearsing favours the primacy effect, since they get rehearsed more.
142
what is chunking?
putting random numbers into meaningful segments. associates with information already in the long term memory.
can only remember about 7 chunks.
143
what is the brown peterson paradigm?
```
given trigram (ie WDL).
count backwards in 3s from a random number to occupy the mind. See how long it takes for the first trigram to decay.after a delay without thinking about it.
```
decays exponentially over 20s
144
what is the phonological confusability effect?
– Errors made by Ss viewing series of letters similar to those
made by Ss trying to discriminate letters against
distracting noise
– e.g. ‘C G V T’ harder to recall than ‘F T K M W’
145
describe the long term store.
verbal worse than visual, less distinct.
duration - near infinite.
capacity - near limitless.
coding - semantic code (at least for verbal).
146
what is the semantically confusability effect?
recall worse if words are semantically similar, ie dog cat cow.
147
what is the partial report technique?
sperling
tachnistoscopic <1 sec presentation of a matrix of letters.
3-4 letters
by the time they had reported it had faded from their sensory memory.
partial report technique - point to one row to recall, could report back any row. They could thus remember all rows immediately.
past 500ms cant recall
```
Iconic Store
= Visual store
- Duration: ~500 msec
- Capacity: 12+ letters (depends on stimuli)
- Loss via: Decay
```
```
for comparison -
Echoic Store = Auditory store
- Duration: ~1-5 sec
- Capacity: (depends on stimuli)
- Loss via: Decay
```
148
describe Anterograde Amnesia
contributed lots of evidence for models.
Inability to make new memories (i.e., cannot transfer new information into LTS)
But intact short-term memory (& LTM prior to incident)
Reduced primacy but intact recency (Baddeley & Warrington, 1970)
149
describe HM
Intractable epileptic seizures.
Scoville removed medial temporal lobes (MTL) bilaterally (both hemispheres).
```
HM had profound anterograde amnesia
• Couldn’t acquire new memories
• Digit span normal
• Memory for past intact (up to 3 years pre-surgery)
• Could acquire some skills
```
150
what is impaired STS?
Normal long-term memory
Impaired short-term memory (poor digit span)
double dissociation data
151
what are problems with the modal model?
Mini-monoliths?
• The stores are presented as ‘unitary’
• Subsequent research has shown that each of the stores is
much more complex
The STS gateway to LTS?
• How can STS-impaired patients transfer info to long-term
memory?
Attention & rehearsal gateway to STS/LTS?
• Implicit learning (‘incidental’, unaware)
• Much unrehearsed info gets into LTS
STS strictly phonological/LTS semantic?
• Non-verbal info? Understand text as you read?
152
what did eriksen and collins show about inter-stimulus intervals?
two seperate stimuli of random dots, together they show 3 letters.
as ISI increased performance declined.
evidence that visual icon decays over -300ms.
153
what did Hogben and Di Lollo say about Eriksen and collins work?
results could have been due to either decay from sensory memory or overlap in visual processing.
decline in performance as ISI
increases because less effective overlap
Persistence of visual information is a phenomenon of visual
processing (not decay from a visual store).
154
what are the 3 phenomena coltheart decribes about sensory store/processing?
‘neural persistence’ (overlap in neural processing)
‘visible persistence’ (overlap in visual processing; Di Lollo)
‘informational persistence’ (icon that decays; Sperling)
~ 150-300 msec
155
what did Haber criticise about iconic memory?
“The demise of the icon”: criticised the study of
iconic memory for lacking ecological validity (no obvious role in daily life):
“The notion of an icon as a brief storage of information
persisting after stimulus termination cannot possibly be
useful in any typical visual information-processing task except reading in a lightning storm.”
156
what is baddeley and hitch's working memory model?
central executive - control centre.
phonological store
visuo-spatial sketch pad.
loop between CE and PS is the articulatory loop/phonological loop. Inner voice used as memory.
157
describe baddeley and hitch's dual task paradigms.
Increase in reasoning time is
significant, but not large (35%)
No effect on errors
It is possible to carry out both
tasks
How is this possible if STS is just a monolithic store?
158
what is the phonological store?
holds memory traces for a few seconds before they fade
159
what is the articulatory/phonological loop?
rehearsal process analogous to subvocal speech (inner voice
160
describe the phonological similarity effect
```
Recall of characters or words is impaired if they are
phonologically similar (Conrad, 1964; Baddeley, 1966)
```
PGVCE is harder to recall than XRFYZ
This effect can be explained because items in phonological
store are based on phonological codes
PGCVE have similar codes in memory, so harder to
discriminate, so harder to recall
161
what is the word length effect?
performance declines as no of syllables increases.
162
what is the word length effect?
performance declines as no of syllables increases.
163
what is articulatory suppression?
Subjects are asked to
articulate irrelevant items
(overtly or covertly) while
performing a verbal span task
Result: word length effect
disappears (for written
words only!)
```
Explanation: Articulation of
irrelevant items dominates
Articulatory Control
Processes, so words cannot
be rehearsed - word length
has no influence
```
164
what is the visuo spatial sketchpad?
A workspace in which an image can be stored and manipulated to guide behaviour.
"Inner eye"
demonstrated by the brooks matrix task.
Ss learn sequence of sentences to remember:
• Spatial (left/right, beneath/above):
– ‘In the starting square put a 1’
– ‘In the next square to the right put a 2’
• Non-spatial (quick/slow, good/bad):
– ‘In the starting square, put a 1’
– ‘In the next square to the quick put a 2’
can build up an internal image.
better at spatial when given auditory.
better at non spatial when written.
165
what is the visuo spatial sketchpad?
inner eye.
166
what is the sketch pad for?
geographical location.
Planning and performing spatial tasks.
Hatano & Osawa (1983) Japanese abacus experts memory for numbers is disrupted by concurrent spatial but not verbal task.
conflict between 2 spatial tasks.
167
what are problems for the working memory model?
Articulatory Suppression
– should prevent registration of words presented visually
(which must be recoded phonologically)
– In fact, span only drops slightly (Baddeley et al., 1994
Neuropsychological data
– In STM patients, visual and verbal spans are similarly
affected (e.g., digit span of 2, visual span of ~4, which shouldn't be the case if independent.
Rehearsal
– How is (non-verbal) visual information rehearsed?
– How do (pre-verbal) children rehearse verbal info without language?
Consciousness
– How can consciousness ‘bind’ information from different
modalities without a multimodal short term store?
– Baddeley (2000) proposed adding an “Episodic Buffer”
168
what are problems for the working memory model?
Articulatory Suppression
– should prevent registration of words presented visually
(which must be recoded phonologically)
– In fact, span only drops slightly (Baddeley et al., 1994
Neuropsychological data
– In STM patients, visual and verbal spans are similarly
affected (e.g., digit span of 2, visual span of ~4, which shouldn't be the case if independent.
Rehearsal
– How is (non-verbal) visual information rehearsed?
– How do (pre-verbal) children rehearse verbal info without language?
Consciousness
– How can consciousness ‘bind’ information from different
modalities without a multimodal short term store?
– Baddeley (2000) proposed adding an “Episodic Buffer”
169
what are the types of rehearsal for LoP?
levels of processing
type I - maintenance rehearsal.
type II - elaborative rehearsal.
only type II increases retention.
Rehearsal makes no difference if you're not actively trying to memorise it.
170
what is the congruency effect/compatibility effect?
remember items given a yes response as opposed to no.
| more pronounced in semantic tasks.
171
what is the congruency effect?
remember items given a yes response as opposed to no.
| more pronounced in semantic tasks.
172
real world evidence for LoP?
• Svenson (1977) – classified students according to how they
read a piece of text
– Surface approach – “I tried to memorise everything”, “I focused
on specific details as opposed to the whole”
– Deep approach – “I tried to identify the principal ideas”, “I
focused on the overall meaning / the author’s points”
deep better
173
what is the elaboration effect?
Different semantic orienting tasks lead to different levels of retention.
ie Could the word ‘watch’ fit into the following sentence?
1. She dropped her ______.
2. The old man hobbled across the room and dropped his ______ in the jug.
2 had better retention.
174
what are problems with the LoP?
circularity?
framework, not a theory.
vague terms like depth and elaboration.
deep processing doesn't always enhance memory.
175
what is episodic memory?
long term.
requires conscious retrieval of unique temporally distinct past experience.
autonoetic
It is conscious recollection that defines the Episodic system.
events
176
what is semantic memory?
long term.
requires consciuos retrieval of knowledge, but no unique retrievable experience.
aware of info but not the origin.
ie london is capital of england.
General knowledge of objects, word meanings, facts,
people,… without connection to a specific time and place.
noetic
facts
177
what is implicit memory?
long term.
unconscious learning, unconscious access via performance.
anoetic
178
what is Tulving's model of long term memory?
episodic leads to semantic and this leads to proceural.
– Learning the meaning of a new word originally requires
an episodic memory
– Over time the meaning becomes assimilated into
semantic memory, and the original learning episode
may be forgotten
– The ability to disconnect information from the context in
which it was learned is a useful property for a memory
system - saves on storage
the distinction between episodic and semantic is useful because in an experiment you may forget which word was presented, but not it's meaning.
179
what is Tulving's model of long term memory?
episodic, semantic and proceural
180
how do you test semantic memory?
attribute verification.
feature generation.
similarity judgement.
lexical decision (given word or nonsense words, judge speed depending on previous relation to last words).
181
how do you test semantic memory?
attribute verification.
feature generation.
similarity judgement.
lexical decision (given word or nonsense words).
182
describe feature-based models of semantic memory.
sensory/functional descriptions:
```
multiple-feature models & neural networks:
list all features
+ Accounts for variety of
category-specific deficits
- Abstract concepts?
```
183
describe feature-based models of semantic memory.
```
sensory/functional descriptions:
+ Accounts for some patient
data (category-specific
deficits)
– Can’t account for all
patients!
```
multiple-feature models & neural networks:
+ Accounts for variety of
category-specific deficits
- Abstract concepts?
184
what is the evidence for distinction between episodic and semantic memory?
Obvious interdependence of two memory systems
makes finding evidence for distinction difficult
Forgetting:
– Episodic memory more prone to forgetting than semantic
• E.g., Bahrick (1984) - 40% of Spanish vocab retained 50y later
anterograde amnesia:
normal semantic memory but deficient episodic memory.
retrograde amnesia:
can affect both.
185
how does fMRI and PET show distinction between episodic and semantic?
Episodic Encoding: left PFC more active
Retrieval: right PFC more active
Semantic retrieval: left PFC more active
186
what is procedural memory?
| describe the mirror task.
Knowledge of how to do things; skills
Acquired through multiple trials, learning by doing
Largely preserved in amnesia!
can measure with mirror drawing, get better over time without episodic memory of it occuring.
187
what is procedural memory?
Knowledge of how to do things; skills
Acquired through multiple trials, learning by doing
Largely preserved in amnesia!
188
what is priming?
| what are the types?
Improvement (speed/accuracy) in processing a stimulus (identification/production/classification) as a result of a prior encounter with the same or a related stimulus.
repetition: long term
repetition: rapid
semantic/conceptual: rapid
189
what are the types of testing for priming?
Perceptual
– Perceptual identification; Word-stem or -fragment completion
Conceptual
– Lexical decision; sentence completion; conceptual decision
190
what is the evidence for the distinction between priming and episodic memory?
Amnesics generally show intact perceptual priming.
Occasionally show impaired conceptual priming.
Right occipital lobe lesion (Patient MS, Gabrieli et al. 1995)
– Showed normal declarative memory (recall, cued recall,
recognition), impaired perceptual priming!
191
what did bartlett propose about schemas?
Bartlett (1932) proposed that:
• Semantic memory is organised in terms of schemas
• Schemas are organised structures that capture our
knowledge and understanding about some aspect of the
world
• Learning and remembering are active processes, and
schemas will help subjects to understand the world
around them
• Memory is a reconstructive process and the
reconstructions are affected by our schemas
• Schemas can also produce distortion
192
how do schemas affect memory?
Selection: They determine what gets encoded
Abstraction: Information gets transformed from the
specific to the general
Integration and interpretation: Schemata “make
sense” of data, or “fill in” missing bits
Normalisation: Memories get distorted so as to fit in
with prior expectations (i.e., existing schemata)
193
what is repeated reproduction?
changed the story to fit with their schema of life.
Story elements conflicted with prior knowledge
(different culture):
– Some aspects downplayed in recall, e.g.:
the supernatural element (‘ghosts’)
– Some details rationalised, e.g.:
‘something black came out of his mouth’ ‘foamed at the mouth’
– More familiar items substituted for less familiar, e.g.:
‘canoes’ ‘boats’
– Dominant details used to anchor the whole story and
make more coherent
the death scene
194
what is a script?
Scripts are a kind of schema that represents commonly experienced events, e.g. going to a lecture.
Activating scripts allows us to use our previous
knowledge of situations to understand world
– e.g. We had tandoori chicken at the Taj Mahal last night
– Hearing ‘tandoori chicken’ activates script for going for
an Indian meal, so it is assumed that the Taj Mahal is a
restaurant, not the real Taj Mahal
195
what kind of graph does forgetting show?
negative logarithmic.
196
what does decay mean?
memory fading over time
197
what does interference mean?
memory traces desrupted or replaced by subsequent or prior learning.
198
what is retroactive interference?
later learning disrupts earlier learning.
199
what is proactive interference?
prior learning disrupts subsequent learning.
interference builds up over trials
• Underwood (1957); Underwood & Keppel (1962):
Performance declines over successive tests with similar
stimuli
200
why does interference lead to forgetting?
Assume a cue has a fixed capacity for activating
memories – the more memories associated with that cue,
the less well it can activate any of them
Or (flipside): If several possible memories share similar
overlap with retrieval environment, successful recall less likely.
201
what are the two main ways of forgetting according to tulving?
Trace-dependent forgetting (=decay, deterioration, loss?)
Cue-dependent forgetting (failure of retrieval)
202
what is the support for cue dependent forgetting?
performance in:
| recognition > cued recall > free recall
203
what is the Encoding-Specificity Principle? (tulving)
```
Retrieval success depends on ‘informational overlap’
between encoding (study) and retrieval (test).
```
Similar to Transfer-Appropriate Processing, but
about context rather than processing.
Context can be Intrinsic or Extrinsic.
204
what does transfer appropriate processing show?
Memory performance depends on the extent to which processes used at Study are the same as those used at Test.
The TAP approach demonstrates that a form of encoding which is ‘shallow’ for one purpose may be ‘deep’ for another.
```
Deep (semantic) or shallow
(rhyme) orienting tasks,
followed by standard
recognition or rhyming test
• Found LoP effect for
recognition test
• But opposite for rhyming
test
• Deep processing does
not always enhance
memory
```
205
describe intrinsic context to the encoding specificity principle.
features that are an integral part of target stimulus.
ie - Study: “They were stuck in a traffic jam”
• Test:
“Cars were moving slowly in the jam” | “They enjoyed eating the jam”
Study:
a) The man tuned the PIANO | b) The man lifted the PIANO
• Cued Recall: a) Something melodious | b) Something heavy
• Congruent condition a-a | b-b: 4.6 words recalled
• Incongruent condition a-b | b-a: 1.6 words recalled
206
describe extrinsic context for the encoding speicificity principle?
Other features present at the time of encoding
(time, place, cognitive state).
Ss learned a list of words on land or underwater
Recall and recognition tested on land or underwater
• Significant recall x encoding context interaction
• Context Dependence (for free recall)
207
what did freud say about forgetting?
people actively(/unconsciously) repress unpleasant memories.
but Child abuse – Those worst abused most likely to remember (Williams,
1994) – contrary to repression.
false recognition or recovered memories:
‘Recovered Memories’ controversy:
– Cases of memories of childhood abuse recovered in therapy
– Danger of influence via interviewer suggestion
208
what is consolidation?
Consolidation is a physiological process, lasting for several hours or possibly even days, that ‘fixes’ information in long-term memory.
New memories are initially 'labile' and sensitive to
disruption before undergoing a series of processes (e.g.,
glutamate release, protein synthesis, neural growth and
rearrangement) that render the memory
representations progressively more stable
209
what is the method of loci for remembering?
• Imagine walking a familiar route (e.g., through your home)
• Visualise 10 locations (in order)
• @Study:
– Visualise the 1st item in the 1st location, and so on.
• @Test:
– Imagine walking past each location, retrieve associated item
210
what is the peg-word technique for remembering?
```
• Visualise words that rhyme with numbers:
one: bun six: sticks
two: shoe seven: heaven
three: tree eight: gate
four: door nine: wine
five: hive ten: hen
• @Study:
– Visualise the 1st item interacting with a bun, 2nd with a shoe,…
• @Test:
– Retrieve the interacting image
```
211
what is face name imagery remembering?
Method:
• Visualise name
– E.g., Taylor – tailor
– E.g., Taylor – sailor (rhyme if name not visualisable)
• Visualise prominent facial feature (be careful here!)
– E.g., beard – imagine a stitched-on beard? bearded sailor?
– In practice: Little evidence that this works
• Difficult to do quickly
• Poorer performance vs. occasional repetition
212
what are verbal mnemonics?
Story formation:
– Useful for serial order, concrete and abstract
– Method:
• Simply make a story that strings the words together
– Works very well, adaptable to any set of words
– Meaningful Encoding
• Deep processing, related to existing knowledge
– Retrieval Structure
• Connected series automatically include cues for next item
– Speed-up
• Extensive practice enables faster encoding and retrieval
213
what is the testing effect?
When trying to learn material, retrieval practice (testing
your knowledge of the material, without looking back at
your notes) improves subsequent test performance
214
what is top down and bottom up selectivity?
Top-down (active, voluntary, endogenous)
Bottom-up (passive, involuntary, exogenous)
215
what is the cocktail party effect?
when lots of conversations are occurring, you must actively focus on one in front of you.
216
what is a dichotic listening task?
Dichotic listening tasks have been used to study how participants selectively attend to target information, and what happens to unattended information.
Ss listen to two messages,
one presented to each ear,
and have to ‘shadow’
(repeat back) one of the messages
Very little information extracted from the non-shadowed message.
Non-attended message
Ss notice basic physical characteristics (e.g. pure tone; change from male to female voice)
Ss do not notice any of the words presented in non-attended message, even when same word repeated
Did not notice when language changed from English to German
217
what is broadbent's theory?
Parallel access to sensory buffer.
Filter allows one through based on physical features.
Other inputs remain in the buffer for later processing.
Filter prevents overloading of the limited-capacity mechanism beyond the filter.
218
problems with broadbents model?
Moray (1959): can hear Own name in unattended ear
von Wright et al. (1975): Dichotic listening task with CS+ (electric shock)
A word was first presented to participants with a mild electric shock. When the same word was later presented to the unattended channel, participants registered an increase in GSR (indicative of emotional arousal and analysis of the word in the unattended channel).
219
what are problems with early selection?
if given dogs, six, fleas in one ear and eight, scratch, two in another.
report dogs, scratch, fleas, eight, six, two.
group together after input has been processed.
against broadbent
220
what is a breakthrough in terms of attention?
only 6%. In the shadowing task, when participants say a word that was presented in the unattended channel
Occurs when word is highly
probably given the context.
may switch between channels.
“I SAW THE GIRL song was wishing”
“me that bird JUMPING IN THE STREET”
against broadbent
221
what is treismans attenuation theory?
Unattended input not completely rejected, but filter attenuates analysis of unattended signal.
Processing proceeds in a hierarchical fashion.
Location of attenuation is flexible.
222
what is the perceptual load theory?
Everyone has limited attentional capacity.
Attentional capacity allocated to main task depends on perceptual load.
Total available capacity always allocated.
Spare capacity is automatically allocated to irrelevant stimuli .
Variable stage of selection
Variable processing of task irrelevant stimuli.
If perceptual load is high: early selection.
If perceptual load is low: late selection.
223
what is a change in marginal interest?
background detail changing
224
what is a change in central interest?
something central to the picture changing
225
what is the cueing paradigm?
Valid cues produced faster responding than neutral cues.
Invalid cues produced slower responding than neutral cues.
Cueing paradigm can be used to investigate what is selected in focused visual attention.
We may selectively attend to
* An area or location or region of space (location-based attention)
* A given object or objects (object-based attention)
* Either to an area of space or a given object (location- and object-based attention)
226
what are the 3 abilities involved in controlling the attentional spotlight?
Disengagement of attention from a given visual stimulus
Shifting of attention from one target stimulus to another
Engaging or locking attention on a new visual stimulus
227
what is inhibition of return?
reduced perceptual priority for information in a region that recently enjoyed a higher priority.
A bias favouring novel locations and objects.
228
what is the zoom lens model?
Attention is directed to a given region of the visual field.
Area of focal attention can be increased or decreased based on task demands.
Probe appeared in
different spatial
locations.
```
Letter task attempted
to focus the p’s
attention on centre of
display. Faster RT
when probe within
central attentional
beam.
```
229
what is object based attention?
Activity in parahippocampal or fusiform gyrus related to whether face or house is attended to – even thought both are in same location
230
what is crossmodal attention?
```
In the real world we often
need to coordinate
information from two or
more sense modalities at the
same time.
```
There are many examples demonstrating vision’s dominance over audition and touch/proprioception.
231
summarise the mental spotlight and zoom models.
The mental spotlight metaphor proposes that attention can be focused on areas (not necessarily related to visual focus). The zoom lens model suggest that the level of detail can vary depending on the task or goals.
232
what is unilateral neglect?
Patient fails to act upon, identify, or acknowledge contralesional stimuli
Patients may fail to eat food on one side of the plate, may draw one side of an object, may read words from one side of a page
Usually after RH damage (neglect of left side) – commonly parietal lobe
One feature underlying unilateral neglect is a difficulty in disengaging the attentional spotlight
tests: line bisection, cancellation, drawing
233
what is endogeneous and exogeneous attention?
exogenous attention—the more automatic, stimulus-driven component of spatial attention.
endogenous attention—the more voluntary, conceptually-driven component of spatial attention.
so if you're in a room talking to someone then you hear a loud noise behind you and turn thats exo.
234
summarise neglect.
Neglect is a neuropsychological condition in which, after damage to one hemisphere of the brain is sustained, a deficit in attention to and awareness of one side of space is observed.
It is defined by the inability of a person to process and perceive stimuli on one side of the body or environment that is not due to a lack of sensation.
235
what are weaknesses of feature integration theory?
Assumption that visual search either all serial or parallel too strong.
Search for conjunctive targets faster than predicted by feature integration theory.
Nature of non-targets in display also important
Some disconfirming evidence from neglect patients
236
what is the threat superiority effect?
using scary or angry pictures instead of stimuli like coloured letters.
argued you respond quicker to them.
237
what is the visual search task used for?
The visual search task is used to study how people identify targets in their visual environment, and whether serial or parallel processes are employed.
238
what does the feature integration theory suggest?
The feature integration theory suggests that there is initial parallel processing of certain features, but that these features are then combined using serial processes.
initial is fast, serial is slower.
239
how does task similarity affect performance?
Treisman & Davies (1973) found two tasks interfered much more when both tasks in same modality. Response similarity also important.
however can be practised to a very high level. ie reading short story while writing down dictated words.
fMRI study found significant brain activity in new area in dual task condition.
selective interference.
240
what is the central capacity model?
Assume there is some central capacity (central executive) which can be used flexibly across a range of activities.
Central processor has limited resources & is sometimes known as attention.
Capacity may depend on arousal (Kahneman, 1973)
Allocation of capacity depends on intentions
Any 2 tasks will interfere provided they require more than total capacity.
241
what is the multiple resource model?
Separate sources of capacity may be specialized for particular processes
Selective interference
It is the type of resources that tasks require that determines whether they will interfere with one another
242
what is the stroop effect?
2 processes competing.
Naming colour : primary task.
Automatic process interferes with primary task.
ie - red in colour yellow
243
describe the emotional pictorial stroop task
colour grading over pictures, have to name colour.
Longer colour naming for ‘emotional’ pictures = both positive and negative image disproportionally captured attention.
Additional interference for snake images by snake phobic participants!
Also Emotional word stroop task. Participant asked to name the colour of word. Research has revealed that individuals that are depressed are more likely to say the colour of a negative word slower than the colour of a neutral word
244
describe what shiffrin and & schneider found about something.
given a list of either 1 or 4 letters or numbers to learn, shown another set and had to say if any matched.
longer RT for varied mapping and no matching letter/number.
245
what is the supervisory attentional system?
Norman & Shallice (1986) distinguished between different levels of automaticity:
1. fully automatic (controlled by schemas; organised plans)
2. partially automatic - contention scheduling – to resolve conflicts between schemas – but without deliberate direction or conscious control
3. deliberate control by SAS :
new tasks, or involve deliberate planning, or strong habitual response has to be prevented (for example, going to hospital rather than work!)
246
what is dysexecutive syndrome?
frontal lobe damage, difficulty in planning, organizing and controlling actions.
247
what is the cognitive bottleneck theory?
Psychological refractory period,
Two stimuli,
Two responses,
Respond to each stimulus as rapidly as possible,
Second stimulus presented shortly after the first one,
A marked slowing to the second stimulus.
There is evidence that there is an attentional bottleneck that prevents the simultaneous processing of any two tasks, whether they are similar or not.
248
when use a stroop task?
The Stroop task may be used to determine which automatic processes interfere with more controlled processes.
249
what are differences between puzzles and real world problems?
```
Puzzles
unfamiliar
involve no prior knowledge
all necessary info. is present in the problem statement
requirements are unambiguous.
```
Real-world problems
familiar require prior knowledge
necessary information often absent solver must ask ‘what is the goal’?
250
what is the behaviourist approach to problem solving?
trial and error.
reproduction of previously learned responses.
Cats learnt to escape initially by chance. Future escapes become progressively faster as the connection between behaviour and reward is learned.
Problem solving was incremental rather than insightful.
251
how do gestalt psychologists characterise problem solving?
both reproductive -
Involves the re-use of previous experience. but functional fixedness problem-solving set.
and productive -
characterised by insight
into structure of problem
and restructuring.
252
what is functional fixedness?
“Support the candle on the wall so that it doesn’t drip on the table below”
P’s often tried to nail the candle to the wall or glue the candle with wax
P’s are fixated on the box’s normal function of holding nails – unable to re-conceptualise it as a candle holder.
Easier if the drawing pins are emptied out of the box before the P arrives
9 dot problem, assume you can't make a line outside of dot grid.
253
what did luchins and luchins show about priming to solving a problem?
Set group = series of problems which could be solved by same complex solution.
Control group = problems needed different solutions.
then TEST problem:
Set group used same complex solution.
Control group used much simpler solution.
254
what is the Kohler Gestalt approach?
various monkey tasks, they would give up but suddenly solve the puzzle.
insight learning
255
what is the space problem theory?
```
Well-defined – solver provided with all info needed to solve problem.
Initial state of problem
Goal state of problem
Legal operators
Operator restrictions
```
towers of hanoi problem.
256
what is the hill climbing solution to problems?
Continually try and more from present state to a state nearer goal.
Need some state evaluation procedure.
But can take you to ‘local high’
Sometimes need to move away from goal to ultimately reach it.
Rubik’s cube – sometimes need to decrease total matches
Walking a dog who goes on other side of a pole. In order to go forward one of you needs to go backwards!
257
what is a means end analysis?
Determine difference between current and goal state.
ie im hungry, i thus need food to not be hungry.
258
what are limitations of the space problem theory?
Research is based on well-defined problems that are not representative of real-life problems
it has questionable ecological validity
It fails to account for Gestalt problem findings
259
what is positive transfer to analogical problem solving?
improved performance as a result of solving a number of similar problems.
260
what is negative transfer to analogical problem solving?
previous experience interferes with the solution to the current problem.
261
isomorphic problems?
identical state space.
ie towers of hanoi and chinese tea ceremony.
transfer 4 rings from one pole to another.
262
homomorphic problems?
similar but not identical structure in a problem.
ie missionaries and cannibals, and jealous husbands.
move miss across river, cant be outnumbered on banks by cannibals.
add wife cant be alone with a husband unless his wife present.
263
benefits to isomorphic problems?
Experience of particular problem can facilitate further attempts at an isomorphic problem (Luger & Bauer, 1978)
(2) Experience of a problem can aid more difficult versions of the same problem (Egan & Greeno, 1974).
264
are homomorphic problems useful?
Experience of particular problem facilitates further attempts at same problem.
Experience with an earlier problem only facilitates a second homomorphic problem if:
(a) second problem simpler than first
(b) hint given that two problems related
265
describe an ill defined problem
little or no information is provided on the initial state, goal state, operators, or some combination of these. Solver needs to define the problem.
ie dunckers radiation problem
266
what is dunckers radiation problem?
‘A patient has an inoperable tumour. The tumour can be destroyed by radiation. Although weak radiation will not harm normal flesh, radiation strong enough to destroy the tumour will. How would you treat the patient?’
267
describe transfer effects between ill defined problems.
told story about general and troops to use in the radiation problem.
Very good at employing an analogy when told to do so and given a hint that it was related.
In all conditions, the most frequent solution was that suggested by the story analogy.
BUT in everyday situation may not be given as hint to use an analogy.
268
describe chess and all that.
computers have infinite space states.
| humans can't replicate all possible scenarios.
269
what's the difference between novice and master chess players?
experiment
remember position of chess pieces for 30s, replicate.
either arranged mid game or randomised.
masters did best in mid game, did worse than novice in randomised positions.
can chunk pieces together (7 chunks not 7 pieces).
```
Hatano and Inagaki (1986) – 2 different types of expertise.
routine expertise (board position knowledge)
adaptive expertise (evaluation knowledge)
```
270
difference between expert and novice physicists?
Experts build better representations of the problems than novices.
Chi, Feltovich and Glasser (1981) – experts and novices sorted physics problems into groups.
- novices sorted according to surface similarities.
- experts sorted according to deep structure
- classified problems in terms of solution principals.
- experts work forwards through the problem.
- novices work backwards through the problem.
271
what makes an expert?
practise makes perfect
chunking
knowledge compilation and rule induction
272
what are the stages of knowledge compilation? Fitts & Posner
Cognitive stage
- Knowledge is declarative, i.e., simply a set of learnt facts
Associative stage
- Recognition and elimination of errors
- Development of procedural knowledge.
- Aspects of the task become linked to each other and to specific situations
Autonomous stage
- Procedures become automatic, and so require less attention.
- Procedures become faster and more accurate
273
what is the ACT* theory of knowledge compilation?
rule based.
Working memory = activated knowledge
Declarative memory = LTM (long term) of world
Procedural memory = LTM of production rules. ‘If xxxxx then xxxxxx’
Knowledge changes from declarative to procedural through ‘proceduralisation’.
- Declarative knowledge can be reported and is non-specific.
- Procedural knowledge is applied automatically, is specific and non-reportable.
Production rules pruned ‘composition’ and tuned in experts.
274
what systems do expert systems use?
Expert systems use ‘if..then’ rules to try and embody human expertise. But difficult to extract this information, difficulties updating info and ethical considerations.
275
what is procedeuralisation?
Knowledge changes from declarative to procedural through ‘proceduralisation’.
- Declarative knowledge can be reported and is non-specific.
- Procedural knowledge is applied automatically, is specific and non-reportable.
276
what is availability heuristic?
People estimate the probability of an event based on how easy that outcome is to imagine or how many examples we can think (or retrieve from memory)
277
what is representative heuristic?
Events that are representative of a class are assigned a high probability of occurrence
People tend to give more weight to anecdotal (personal) information, compared to statistical information
how well an item fits with other existing data
The representativeness heuristic leads people to overestimate the frequency of events that are deemed representative of their class.
278
what is base rate neglect?
Ignore prior knowledge when estimating probable outcomes.
Base rate neglect is a fundamental flaw in human reasoning, resulting from our weakness in analyzing complex probability problems. It is an example of where our intuitive judgements or instincts can lead us astray.
can include representative heuristic?
279
what are possible processes of decision making?
Algorithm
Systematic rule that is guaranteed to produce the correct solution…
Heuristic
Mental shortcut, rule of thumb, that will produce a good enough estimate, or be correct most of the time…
280
what is loss aversion?
People are much more sensitive to potential losses than potential gains
e.g. gain £20 if a tossed coin came up heads and a loss of £10 if it came up tails
Most people refuse the bet
281
what is the sunk cost effect?
$100 non-refundable deposit for weekend
Become unwell on way there
Would feel better at home
Drive or turn back?
GO : $100 + other expenses + feel miserable
DON’T GO: $100 + no other expenses + feel better
people feel inclined to go once they have spent money.
282
what is a framing effect?
the phrasing of a question or example.
If Program A is adopted, 400 people will die.
If Program B is adopted, there is 1/3 probability that nobody will die, and 2/3 probability that 600 people will die.
B sounds more appealing since A negatively framed.
283
what is an omission bias?
tolerate risks if they are smaller than original option.
Anticipated emotions may be important in decision making, for instance with anticipated regret in the case of omission bias.
284
what is prospect theory?
Prospect theory suggests that important factors in decision making are loss aversion and risk aversion.
