Exam Flashcards
(210 cards)
1
Q
Two issues when using animals in brain-behaviour research
A
- Do animals contract the same neurological diseases that humans do?
- Ethical issues
2
Q
Which types of disorders are easier to model in animals, neurological or behavioural?
A
Neurological
3
Q
SHR rats are good models for which disorder?
A
ADHD
4
Q
Guidelines on using animals in research (4)
A
- Only acceptable is it contributes to understandings that will benefit humans
- Optimal standards for animal health and care
- Maintain public confidence
- Can only use animals if that is the only way to do the research and must use the smallest number of animals
5
Q
Staining cerebral neurons
A
Allows visibility of the cells
6
Q
What brain region shows decreased volume in Parkinson’s Disease?
A
Substantia Nigra
7
Q
Neuropsychology
A
Study of the relations between brain function and behaviour
8
Q
Behavioural Neuroscience
A
Study the biological basis of behaviour
> in humans and in animals
9
Q
What is the swim test what two types of place learning does it demonstrate?
A
Swim test : rat must find platform using external cues
Matching-to-place learning = platform is in the same location each trial, but a different location each day
Landmark Version = platform is identified by a cue on the wall
10
Q
What are 2 reasons for modifying the brain and seeing how behaviour is altered
A
- Develop hypotheses about how the brain affects behaviour
2. Test the hypotheses
11
Q
Ablation
A
Removal or destruction of tissue
12
Q
Stereotaxic Apparatus
A
A surgical device that permits the researcher to target a specific part of the bran for ablation
13
Q
2 Types of brain lesions
A
Electrolytic Lesion - destroying region using an electric current through an electrode
Neurotoxic Lesion - a chemical is injected to kill neurons
14
Q
How do chemicals control behaviour?
A
Genes control the cell’s production of chemicals, so it is possible to relate behaviour to genes and to chemicals inside and outside the cell
15
Q
What is microdialysis?
A
A technique use to determine the chemical constituents of extracellular fluid
16
Q
How can researchers tease apart nature and nurture for behaviour
A
Study twins and adopted children
17
Q
What part of a gene do we relate to behaviour
A
Specific alleles
18
Q
What do brain-derived neurotrophic factors (BDNF) do
A
They play an important role in stimulating neural plasticity
19
Q
Twins have nearly ____ patterns of gene expression early in life, but _______ by the age of _____
A
Identical
Different
50
20
Q
What does the Corsi block-tapping test test?
A
Short term recall of spacial position
21
Q
What does the mirror drawing task test?
A
Procedural memory
22
Q
What does the recency memory task test and how?
A
It challenges assumptions about memory by getting participants to identify which picture they saw most recently
23
Q
Transcranial magnetic stimulation
A
A non-invasive procedure that uses magnetic fields to stimulate nerve cells in the brain.
It is non-specific
24
Q
What are the 4 major techniques for measuring the brain’s electrical activity
A
- Electroencephalography (EEG)
- Event-related potentials (ERP)
- Magnetoencephalography (MEG)
- Single-cell recording
25
EEG
Measures the summed graded potentials from many thousands of neurons
26
What the EEG reveals about features of the brain's electrical activity
1. EEG changes as behaviour changes
2. Records from the cortex and displays an array of patterns
3. The living brain's electrical activity is never silent
27
Event-Related Potentials (ERPs)
EEG related to to a specific sensory event in a specific point in time
> A pattern related to a specific stimulus
28
Advantages of ERP
Non-invasive
| Low cost
29
How ERPs record electrical activity
ERPs can be used not only to detect which areas of the brain are processing particular stimuli but also to study the order in which different regions play a role
30
How do researchers measure single-neuron action potentials
Use electrodes placed next to cells or inside the cells
31
Place cells
Neurons maximally responsive to specific locations
32
Computerized Tomography (CT scan)
X-ray beam passed through the brain at many different angles creating many different images
> Images are combined to create a 3D image of brain
33
Magnetic Resonance Imaging (MRI)
Technique that produces a static 3D brain image by passing a strong magnetic field though, followed by a radio wave, then measuring the radiation emitted from hydrogen atoms
34
Diffusion Tensor Imaging (DTI)
Detects the directional movements of water molecules to image nerve fibre pathways in the brain
35
What are DTI imaging used for
Used to delineate abnormalities in neural pathways
36
Functional Magnetic Resonance Imaging (fMRI)
Measures the oxygen/blood flow in the brain that indicates which brain regions are active
37
Resting-State MRI (rs-MRI)
Used to infer brain function and connectivity by studying fMRI signals when participants are "resting"
38
Positron Emission Tomography (PET)
Detects the changes in blood flow by measuring the metabolic activity of neurons
39
Advantages of PET
- Allows the mapping of a wide range of brain chances and conditions
- Can detect relative amounts of a given neurotransmitter, the density of receptors, and metabolic activities associates with learning, brain poisoning and degenerative processes
40
How to detect differences with PET
Take images at many times and then compare them. The difference of the scans are averaged to produce the representative image
41
Near-Infrared Spectroscopy (NIRS)
Non-invasive technique that gathers light transmitted through cortical tissue to image blood-oxygen consumption
42
Advantage and disadvantages of NIRS
Advantage: Easy to hook up
Disadvantage: Measurement restricted to cortical activity (light does not penetrate the brain very far)
43
3 Perspectives on brain development
1. Structural development can be studies and correlated with the emergence of behaviour
2. Behavioural development can be analyzed and predictions can be made about what underlying circuitry must be emerging
3. Factors that influence both brain structure and behavioural development , such as large injury, can be studied
44
At what day are the forebrain, midbrain and hindbrain visible during development?
About day 28
45
Prenatal Stages
```
Zygote = up to 2 weeks
Embryo = 2-8 weeks
Fetus = 9 weeks to birth
```
46
What is the neural plate and when does it emerge?
It is a thickened region of the ectodermal layer that gives rise to the neural tube.
It develops at 3 weeks
47
What is the neural tube?
Structure in the early stage of brain development from which the brain and spinal cord develop
> Neural plate folds to form tube
48
```
What are the major events that happen on day:
49
60
100
7 months
9 months
```
49: embryo begins to resemble a person
60: sexual differentiation
100: brain looks distinctly human
7 months: gyri and sulci begin to form
9 months: brain looks like adult brain
49
Neural Stem Cell
A self-renewing multipotent cell that gives rise to neurons and glia
50
What happens when neural stem cells divide?
It produces 2 stem cells; one dies and the other lives to divide again
51
Where does the first neurogenesis occur?
Sub ventricular zone
52
Progenitor Cell
Precursor cell derived from a stem cell, it migrates and produces a neuron or glial cell
Also produces nondividing cells knows as neuroblasts and glioblasts
53
Neuroblast
Product of a progenitor cell that gives rise to different types of neurons
54
Glioblast
Product of a progenitor cell that gives rise to different types of glial cells
55
How do stem cells know what to become?
Chemical signals -->
Turns genes on (gene expression) -->
Specific proteins are made -->
Specific cells
56
Methylation in epigenetics
Blocks transcription or translation
57
Neurotropic Factor
A chemical compound that acts to support growth and differentiation in developing neurons
58
7 Stages of brain development
1. Cell birth (neurogenesis, gliogenesis)
2. Migration
3. Differentiation
4. Maturation
5. Synaptogensis
6. Cell death
7. Myelination
59
Brain development as a function of time vs brain and body weight
Graph in pictures
60
Which 2 disorders are associated with insufficient synaptic pruning?
Autism and schizophrenia
61
When is cell birth mostly complete?
About 5 months
62
When does cell migration start?
Begins shortly after neuro/gliogenesis and continues for 6 weeks after it is finished
63
Radial Glial Cell
Path making cell that a migrating neuron follows to its appropriate destination
64
When does cell differentiation start?
Begins after cells have begun to migrate
65
What is the progression of the cortical layers of cell migration
Cells migrate to inner layers and then to outer layers (layers 6-1)
66
What are the 2 kinds of neuronal maturation
Dendritic growth
| Axonal growth
67
Tropic vs Trophic
```
Tropic = guiding
Trophic = nourishing
```
68
When does synaptic development start?
5th gestational month
69
In what way does synaptic pruning occur?
Front to back, synaptic connections that are not part of a functional network are pruned away in an experience-dependent manner
70
Which region is last to mature and when does it happen
Frontal lobe, around 20
71
When does glial development happen?
After most neurogenesis is complete
| > continues throughout life
72
Behaviours cannot emerge until what happens?
Until the requisite neural machinery has developed
73
Language onset starts when and is finished by what age?
Starts at 1-2
| Finished by age 12
74
Chemoaffinity Hypothesis
| Prenatal
Neurons or their axons and dendrites are drown toward signalling chemicals that indicate the correct pathway
75
What effects neural connectivity postnatally?
proceeds in an activity-dependent manner
76
Critical Periods
A developmental "window" during which some event has a long-lasting influence on the brain
77
What 2 things can cause abnormal experience and brain development?
Early deprivation of sensory experience and early deprivation of social experience
78
What has early life stress been associated with?
Increased amygdala
Decreased hippocampus
Later development of depression and anxiety disorders
79
What does testosterone and estrogen affect in the development of the brain?
- # neurons formed
- # of neurons that die
- Cell growth
- dendritic branching
- synaptic growth
- activity of synapse
80
What is the worst time for injury during brain development?
Last half of intrauterine period and the first few months after birth
81
What is the least harmful time for brain damage?
The first few years after birth
| > brain is more able to adapt
82
What happens if the neural tube does not close completely?
Spina Bifida
| Spinal cord abnormality that is associated with serious motor problems
83
What is anencephaly?
Front end of neural tube does not close so forebrain does not develop
> infant dies
84
Impaired cognitive functioning due to abnormal brain development
- Genetic abnormalities (down syndrome)
- Prenatal exposure to infections (rubella) or toxins (alcohol)
- brain trauma (anoxia)
- malnutrition
85
Brain regions associated with emotion and motivation
Hypothalamus
Limbic system
Frontal Lobes
86
A persons' motivation can be determined by their state of:
Hormones
| Chemical Senses
87
Has a link been found between drives and brain activity?
No
88
Behavioural change correlates with changes in:
Hormones and cellular activity
89
What do chemosignals do?
They play a central role in motivated and emotional behaviour
90
What is the mechanism of smell?
- Chemicals we breathe dissolve in mucus and interact with cilia
- olfactory receptors project to the olfactory bulb
91
Which somatosense does not project to the thalamus?
Olfaction
92
What is the mechanism of taste?
Each of the 5 different receptors respond to a different chemical component of food
93
Innate Releasing Mechanism
Pre-wired mechanisms that detect specific sensory stimuli and direct an organism to take a particular action
94
Learned Taste Aversion
Acquired association between a specific taste or odour and illness.
Leans to an aversion to that food
95
Regulatory Behaviour
Behaviour motivated to meet the survival needs of the animal, controlled by homeostatic mechanisms
96
Non-Regulatory Behaviour
Behaviour that is unnecessary to meet the basic survival needs of the animal
Influenced by external stimuli and controlled by frontal lobes
97
Pituitary Gland
Gland beneath hypothalamus, secretions control the activities of many other endocrine glands
98
Lateral region of the hypothalamus
Contains nuclei and nerve tracts that connect the lower brainstem to the forebrain
99
Medial Forebrain Bundle
Dopamine fibers that are involved in reward and motivating behaviour
100
Posterior pituitary
Neural tissue, continuation of the hypothalamus
101
Anterior Pituitary
Glandular tissue, synthesizes various hormones
102
Hormones of Pituitary table
Picture
103
Factors involved in controlling hypothalamic hormone-related activity (3)
Feedback Loops: control the amount of hormone that is released
Neural Regulation: other brain regions influence hormone release
Experiential Responses: experience can alter the structure and function of hypothalamic neurons (sensitization or habituation)
104
The amygdala is multimodal, what does that mean?
Many neurons respond to more than one sensory modality
105
Where does the amygdala project to?
Primarily to the hypothalamus and brainstem
106
The role in the prefontal cortex and motivation
Selecting behaviours appropriate to the particular time and place
Adapting
107
Bigger picture of the circuitry of the brain
The upper regions of the brain influence the lower regions, and the lower regions influence the upper regions
108
3 components of emotion
Autonomic Responses
Subjective feelings
Cognitions
109
James-Lange view of emotion
Physical arousal comes first and the brain interprets this as emotion
110
Somatic Marker Hypothesis
"Marker" signals arise from emotions and feelings act to guide behaviour and decision making, usually an unconscious process
111
What happens when there is damage to the prefrontal cortex?
- Inability to recognize emotions in self and others
- Apathy
- Inability to plan
112
What are 3 components of eating disorders?
digestive system
hypothalamus
cognitive factors
113
Aphagia, what lesion causes it?
Failure to eat
| > Lesion of lateral hypothalamus
114
Hyperphagia, what lesion causes it?
Disorder of overeating
| > Lesion of ventromedial hypothalamus and the paraventricular nucleus of the hypothalamus
115
What are the 2 kinds of thirst?
Osmotic Thirst = results from increased concentration of chemicals in body fluid
Hypovolumic Thirst = produced by a loss of overall fluid volume from the body
116
What parts of the brain are sexually dimorphic?
Hypothalamus
Amygdala
Prefrontal cortex
Spinal cord
117
Reward has two independent processes:
Liking and wanting
118
What techniques are used to measure sleep?
Electroencephalogram (EEG)
Electromyogram (EMG)
Electrooculogram (EOG)
119
Rhythm of sleep urge vs need
They look pretty much the same but there is a spike in sleep urge in the afternoon without spike in sleep need
120
Do people dream in NREM?
Yes, but they are not as vivid as REM dreams
121
What physiological activities take place during NREM?
Decreased body temperature and increase in growth hormone release
122
What abnormal behaviour can occur during NREM
Sleep talking
Sleep walking
Night Terrors
123
What happens to people's muscles during REM?
Atonia = no tone, inhibition of the motor neurons
124
What happens to body temperature during REM?
Mechanisms to regulate temperature stop working so body temp moves towards room temp
125
How is sleep biologically adaptive?
Sleep conserves energy
| --> When not searching for food animals sleep to conserve energy
126
Basic rest-activity cycle
Recurring cycle of temporal packets (90 min for humans) during which an animal's level of arousal waxes and wanes
127
Sleep as a restorative process hypothesis
Chemical events that provide energy to cells may be used up during waking and replenished during sleep
128
What is insomnia
Disorder of slow-wave sleep resulting in prolonged inability to sleep
129
REM behaviour disorder
Associated with vigorous movement during REM sleep
| > damaged pons
130
Narcolepsy
Sleep disorder characterized by frequent periods of sleepiness
131
Somnambulism
Sleep walking
132
Biorhythm
Inherent timing mechanism that controls or initiates various biological processes
133
What brain region is the "master clock"
Suprachiasmatic Nucleus
134
What happens if the suprachiasmatic nucleus is damaged?
All daily activities occur haphazardly
135
When are suprachiasmatic cells most metabolically and electrically active?
When it is light out
136
What is the metabolic cascade maintains the circadian rhythm
Feedback loop in which proteins are first made and then combine to make a dimer. The dimer inhibits the production of its component proteins. When the dimer degrades the process restarts
> it is a perfect 24 hour cycle
137
What is the free running rhythm in a human
A rhythm that does not have anything controlling it
| >> A human's cycle will become 25-27 hours
138
How does light affects the circadian rhythm
Light coming in will go directly to the SCN and it starts the cycle every day
139
Zeitgebers
Environmental event that entrains biological rhythms; a "time giver"
140
Entrainment
Determine or modify the period of biorhythm
141
Retinohypothalamic Tract and the SCN
The pathway that is independent of vision that queues the circadian rhythm
142
In order to learn what must you have?
Brain plasticity
143
Implicit memory
Unconscious memory
| >> Bottom up, information is encoded in the same way it is perceived
144
Explicit memory
Conscious memory
| >> Top Down, subject reorganizes info before it is encoded
145
Learning set
An understanding of how a problem can be solved with a rule that can be applied in many different situations
146
Declarative memory
Ability to recount what one knows, to detail the time, place and circumstances of events
147
Procedural memory
Ability to recall a movement sequence or how to perform some act or behaviour
148
What brain region is involved in short term memory?
Frontal lobes
149
What brain region is involved in long term memory
Temporal lobes
150
Is the severity of memory loss related to the location or the size of damage
Size
| There does not seem to be one specific locus of memory
151
What are the benefits of having the neocortex project to the enterhinal cortex and then back again?
It allows the memory to evolve with experience
152
All sensory systems project to what part of the brain?
Frontal lobes
153
What does it mean when the hippocampus consolidates new memories?
In consolidation, or stabilizing a memory trace after learning, memories move from the hippocampus to diffuse regions in the neocortex
154
Reconsolidation
The process of restabiliziing a memory trace after the memory is revisited
155
Proposed Circuit for Implicit memory
Basal ganglia
Ventral thalamus
substantia nigra
premotor cortex
156
Proposed neural circuit for explicit memory
Temporal lobe structure
Frontal lobe structure
Medial thalamus
Basal forebrain-activating system
157
Emotional memory
Memory for the affective properties of stimuli or events
| > can be implicit or explicit
158
What can be used to infer synaptic changes?
The number of dendrites
159
Where does neurogenesis happen in the adult brain?
```
Subventricular zone (migrates to olfactory bulb)
Dentate gyrus
```
160
What happens to dendritic spines in high and low estrogen?
High: more spines in hippocampus
Low: more spines on neocortex, less in hippocampus
161
Nerve growth factor
Neurotrophic factor that stimulates neurons to grow dendrites and synapses, and in some cases, promotes the survival of neurons
162
Behavioural sensitization
Escalating behaviours response to the repeated administration of a psychomotor stimulant
>>Associated with increased number of receptors, synapes and dendrites
163
7 Guiding Principles of Brain Plasticity
1. Behavioural change is reflected in the brain
2. All nervous systems are plastic in the same general way
3. Plastic changes are age-specific
4. Prenatal events can influence brain plasticity throughout life
5. Plastic changes are brain-region dependent
6. Experience dependent changes interact
7. Plasticity has pros and cons
164
Long term potentiation
A strong burst of electrical stimulation applied to the presynaptic neuron produces an increase in the amplitudes of the EPSP in the post-synaptic neuron
165
Long-term Depression
Neuron becomes less active in response to repeated stimulation
166
Neurochemistry of Long Term Potentiation
Glutamate is released and readily binds to AMPA receptors, but not to NMDA receptors because Mg is blocking it
Must have sufficient concentration to bind to NMDA receptors
Once NMDA receptor is stimulated it allows Ca+ in, which results in more AMPA receptors being created
167
What are some challenges to diagnosing behavioural disorders?
- People are not objective about their behaviour
| - Not usually specific identifying symptoms
168
What are research challenges to investigating behavioural disorders?
- The brain has many different cell types
| - Connections in the brain are always changing
169
What is a disadvantage of compensatory plasticity when trying to research a slowly progressing disease
The brain has a remarkable capacity for adapting, so the disorder might be far along before symptoms arise
170
What is one limit of technology in terms of identifying brain disorders?
Technology cannot yet detect subtle neuronal changes
171
Limitation of using animal models
They provide an over simplified view of the neurobiology behind behavioural abnormalities
172
How many people suffer from a diagnosable mental disorder/
1 in 4
173
3 general types of psychiatric disorders
1. Psychosis
2. Mood
3. Affect
174
Summary of DSM
In pictures
175
Stem cell therapy
Aims to return a dysfunctional brain region back to it's embryonic state and regrow a normal region
176
Electroconvolsive Therapy
Uses electrical current to produce seizures as a treatment for severe depression because it stimulates the production of neurotrophic factors
177
Drug to treat schizophrenia
Neuroleptics
178
Drug for anxiety
Anxiolytics
179
Anti-depressants
Selective serotonin reuptake inhibitors
180
Drug to treat Parkinson's
L-DOPA
181
Limitation of pharmacological treatments
The drugs just treat the symptoms, they do not provide the behavioural tools needed for coping
182
Behavioural Therapy
Treatment that applies learning principals to eliminate unwanted behaviours
183
Cognitive therapy
Treatment of emotional disorders requires a changing of maladaptive patterns of thinking
184
Neuropsychological therapy
Aim to retrain people in the fundamental cognitive processes they have lost
185
Emotional Therapy
Talking about emotional problems thereby enabling people to gain insight into their causes
186
Real time fMRI as a behavioural treatment
Individuals learn to change their behaviour by controlling their own patterns of brain activation
187
What is virtual reality therapy most effective at treating
PTSD
188
What is the point of all the behavioural therapies?
They are promoting plasticity
189
Ischemia
Lack of blood to the brain as a result of stroke
190
Constraint-induced therapy
After a stoke if a patient has decreased function of one side of the body, the strong limb is restrained so they are forced to use the weaker limb
191
What are the 2 types of seizures?
Symptomatic Seizure = identified with a specific cause
| Idiopathic seizure = does not seem to have a specific cause, seems to be spontaneous
192
How can you treat epilepsy?
Use anticonvulsant medications that act on GABA --> Inhibit the discharge of abnormal neurons by stabilizing the neuronal membrane
Surgical removal of abnormal tissues
193
What happens in the body with Multiple Sclerosis?
There is a loss of myelin in the motor and sensory nerves, and sometimes axons are destroyed
194
2 types of dementia
Degenerative = presumed to have a degree of genetic transmission
Non-Degenerative = non-genetic disorders caused by many different things
195
What degenerates in Parkinson's disease?
Deterioration of the substantia nigra and loss of dopamine
196
Positive symptoms of Parkinsons
Tremor at rest
Muscular rigidity
Involuntary movements
197
Negative symptoms of Parkinson's
Disorders of posture
Balance problems
Disorders of locomotion
198
Treatments for Parkinson's
Physical Therapy
L-DOPA
Surgical
Transplantation
199
Why is L-DOPA not a long term treatment for Parkinson's
cannot work long term because even if it increases dopamine, it does not matter if there are no receptors
200
Buldups in the brain that cause Alzheimer's disease
Amyloid Plaques - in the cerebral cortex
Neurofibrillary Tangles - cerebral cortex and hippocampus
201
What areas of the brain are most effected in the degeneration in Alzheimer's
Limbic cortex
Inferior temporal cortex
Posterior parietal cortex
--> Hippocampus
202
In Alzheimer's, cerebral atrophy may be due in large part to the loss of ______
Dendritic arborization
203
What disorder has the highest genetic link, what % is it?
Schizophrenia
| Up to 70% genetic
204
Common brain abnormalities in Schizophrenia (3)
1. Large ventricles and thinner cortex in medial temporal and frontal regions
2. Composition of neurons and fibers of temporal and frontal lobes are changed
3. Abnormal dendritic fields in cells of dorsal prefrontal regions, hippocampus and entorhinal cortex
205
Antidepressants act to increase the levels of which 2 neurotransmitters
Serotonin
| Norepinephrine
206
Neuroplasticity hypothesis of depression
Suggests that depression may involve low levels of neurotrophic factors
>> Growth factors are down-regulated by stress and up-regulated by antidepressants
207
What is the most effective treatment for depression?
A combination of cognitive behavioural therapy and medication
208
What makes anxiety disorders so tricky?
They often never occur alone
They make other disorders worse
Prevalence: 4 out of 10 people have it
209
Brain region activation with anxiety disorders
Increased activation in the cingulate cortex and parahippocampal gyrus
Enhanced response to anxiety provoking stimuli in the amygdala and prefrontal cortex.
210
Diagnosis Challenges (7)
1. Organizational Complexity - many cell types
2. System complexity - everything is linked
3. Neural Plasticity
4. Compensatory plasticity - cannot see problem because another brain region takes over
5. Technological resolution - cannot see small changes or small problems
6. Modeling simplicity - neurobiology in animals is oversimplified
7. Modeling Limitations - animal models cannot properly mimic human disorders
