after midterm 2 Flashcards
1
Q
possible causes of lesions
A
stroke, tumor, traumatic injury, certain brain diseases
2
Q
types of static/structural brain imaging
A
dissection, X-ray, CT/CAT, MRI
3
Q
X-ray
A
accidental discovery, discovered at end of 19th century, limited in ability to show 3-dimensionality or exhibit high resolution
4
Q
CT scan
A
a bunch of x-rays and use computer technologu to reconstruct a higher resolution from the high amounts of data
5
Q
MRI (magnetic resonance imaging)
A
based on NMR and depends on the property of an atomic nucleus called nuclear spin; a lot of water in body and look different in different chemical environments leads to a lot of data and how make MRI
6
Q
scale of magnetic field used for MRI mac
A
3 teslas
7
Q
types of dynamic/functional brain imaging
A
surgical recording, ECoG, EEG, MEG, fMRI, PET
8
Q
surgical recording
A
Wilder Penfield did brain mapping using electrical stimulation of brain and recording what happened
9
Q
ECoG
A
electrocorticography - electrodes placed directly on the brain, used to map seizure origins in order to remove epileptogenic tissue; higher spatial res than EEG
10
Q
EEG
A
electroencephalography - electrodes on the surface of the scalp and detects neural activity thru the origin of electrical field changes; is a method of recording some kind of summed activity in the brain
11
Q
temporal and spatial resolution of EEG
A
spatial - cm
temporal - ms
(low area resolution but high temporal)
12
Q
who performed first EEG recording
A
Hans Berger in the 1920s
13
Q
who started ECoG recordings
A
Penfield (1940s-50s)
14
Q
EEG gives average of
A
global average of billions of neurons
15
Q
MEG
A
magnetoencephalography - measures magnetic field induced by electrical currents associated with brain activity using SQUID technology; is difficult bc have to measure very weak fields and is therefore also expensive, also computationally challenging to reconstruct data
16
Q
SQUID technology
A
Superconducting Quantum Interference Device
17
Q
PET scan
A
positron emission technology - tracks positron emission of radioactive chemicals in blood and locates locations of high neural activity; specifically tracks the 2 gamma rays emitted in opposite directions when positrons collide w electrons
18
Q
spatial and temporal resolution of MEG
A
spatial - mm
temporal - ms
19
Q
spatial and temporal resolution of PET
A
spatial - cm
temporal - sec -min
20
Q
what device is necessary for PET
A
cyclotron in order to make radioactive atoms via accelerated collision
21
Q
purpose of F-18 specifically
A
injected into blood, if F-18 incorporated into glucose, can follow this “glucose” and measure it
22
Q
fMRI
A
functional MRI - series of MRI images over time by tracking BOLD signal when in regions experiencing inc neural activity
→ fMRI BOLD (blood oxygen level dependent) signal : measure of oxygen delivery to different parts of brain w/ assumption that more active parts will need more oxygen
23
Q
nuclear spin and NMR
A
in a magnetic field, spin can align in 2 different energy states; there proton-NMR signals for various molecules that show the energy necessary to flip the spin for different molecules
24
Q
tesla and gauss relationship
A
1 tesla = 10,000 Gauss
3 tesla is 60,000 times geomagnetic field
25
what are the PET isotopes
F-18, O-15, C-11
26
brain electrical oscillation ranges (delta, theta, alpha, beta, gamma)
Delta < 4Hz; theta: 4-8 Hz; alpha: 8-15 Hz; beta: 15-30 Hz; gamma > 30 Hz
(are associated w EEG as different frequency components)
27
spatial and temporal resolution of fMRI
spatial - mm
| temporal - s
28
hemoglobin and its relationship w fMRI
hemoglobin is an oxygen carrying protein in the blood, and MRI signal changes based on whether hemoglobin has oxygen on it or not;
29
how is BOLD signal tracked
BOLD tracks hemoglobin (O-carrying protein in red blood cells) from oxygenated to deoxygenated form by following H’s on surrounding water
30
"dark energy"
brain operating at nearly same level no matter what u are externally doing --> what is ur brain doing???
31
palindrome
a word or phrase that reads the same backwards and forwards
32
honeybee waggle dance
communicate angle from sun w lil dance
33
Karl von Frisch
dude who studied honeybees and discovered all the honeybee stuff
34
broca's aphasia
production aphasia for spoken and written language identified due to a lesion of left frontal lobe
35
wernick's aphasia
comprehension aphasia for spoken and written language due to left posterior temporal/parietal lobe lesion
36
wada test
put to sleep one half of brain by injecting a small amount of barbiturate sedative hypnotic in one artery going to brain (are two main ones that go to different hemispheres)
37
cerebral lateralization of language
almost all language issues due to lesions in the left hemisphere
38
where have language in the brain
For right handers, (97% have in left hem, 3% have in RH)
| For non-right handers (70% have in LH, 15% have in RH, 15% have in both)
39
aphasia
neurologically-based impairment in language function
40
location of lesions for Brocas
left frontal premotor area
41
location of lesions for Wernicke's
posterior left temporal lobe
42
what was Wada test originally used for
formerly used to determine where language centers are when trying to excise seizure loci
43
what are linguistic mirror neurons
participate in both observing language and generating, in Broca's area
44
corpus callosum
in between and connects the two hemispheres of the brain
45
Roger Sperry's experiments were on?
were on consequences of severing corpus callosum (meaning 2 hemispheres of the brain r completely split)
46
Roger Sperry's experiments were
Image flashed very quickly to either left or right visual space; flash a spoon on right visual field, can say what they saw b/c LH usually lang-dominant; flash spoon on left visual field, usually say dont know what it is; HOWEVER can choose spoon out of objects even if cant articulate it
47
cerebral lateralization of functions
right hemisphere - spatial patterns and functions, nonverbal linguistic, visual gestalt/perspective, harmony, timbre
left hemisphere - language, calculation, visual detail
48
cortical neuropil
an electrodynamic structure of extraordinary capacity; any area of mostly unmyelinated axons, dendrites & glial cells densely packed together; gaps <20nm, >1 mil synapses in 1mm^3 of neuropil
49
Walter Freeman and brain neurodynamics
A lot of EM activity → EM fields that are all pushing on eachother; very complex EM interaction; “superfluid like transitions in EEG”
50
STM vs LTM
short term memory/working memory has limited capacity and is transient; long term memory is initially fragile, gets to long term by consolidation (helped by rehearsal and review) and structural change
51
Karl Lashley
tried to localize where memory happening in the brain w rat maze experiments in the 1920s
- Once the rat memorized the brain, would lesion different parts of the brain to find when rat no longer remembered maze
52
conclusion of Karl Lashley's rat maze experiments
Only correlation was that the more messed up the brain was, the more errors rats made and could not pinpoint specific spot where memory is
→ memory not localized but distributed
53
H.M (Henry Molaison)'s issues
Severe seizures since age 10, had surgery at age 27 in 1953, an experimental surgery to try to remove part of brain causing seizures; targeted area with amygdala and hippocampus
→ ended up removing entire hippocampus
54
result of removing HM's hippocampus
WM okay and old LTM okay (remembered stuff from before had surgery)
But, could not learn any new information
(also, dec memory was gone but non-dec memory was intact)
55
conclusion from HM
Concluded from HM that hippocampus a hub of distributed storage and consolidation, hub of distributed activation that helps form networks of connections that represent memories
56
declarative vs non-declarative memory
Declarative : can explain something
| Non-declarative : stuff can do but cant explain how; example is riding a bike
57
corpus callosotomy
disconnecting of direct neural pathways between the two hemispheres of the brain, resulting in "split brain" patients
58
drawing of shapes in split brain patients
drawing box with bad hand (left): more like box but squiggly whereas right wasn’t at all like box; motor control contralateral so left-handed drawing controlled by right brain; suggests R-hemi superior in global spatial analysis
59
ephaptic coupling
generation of local electric fields influence nearby cells
60
neural correlates of consciousness (NCC)
neural conductors sufficient for manifestation of conscious awareness; whole brain is imp for consciousness weee
61
correlation b/t sleep time and metabolic rate
large animals (slower met rate?) tend to sleep less
62
circadian means
daily
63
examples of circadian rhythms
sleep, body temperature, melatonin synthesis by pineal gland, cellular metabolism and neuronal activity; in plants the closing and opening of flowers and leaves
64
other biological rhythms
annual or circannual (migratory activity of birds and animals); other periods : cycles of ovulation in female animals
65
SCN (suprachiasmatic nucleus) in hypothalamus
Primary site of biological clock in vertebrate animals
SCN neurons in culture will have rhythm; SCN oscillator is coupled to the rest of the brain
- located in diencephalon (top of brainstem)
- named bc above optic chiasm
- 20k neurons with circadian periodicity of neural firing independent of brain or body
66
light input for SCN
retinal hypothalamic pathway; 1% of RGCs (retinal ganglion cells) connect w SCN and tells circadian rhythm whether light or dark
67
Circadian rhythm of melatonin secretion
high amounts during the night and triggers clockwise behavior in rest of body
Melatonin secretion shifted by light input to SCN
68
bright light near bedtime
correlated with increased difficulty falling asleep; neg affects circadian timing and next morning alertness
69
sleep stages - different stages in EEG appearances
stages 1-4 are non-REM sleep
stages 3-4 are slow wave sleep (SWS) ,10Hz
REM sleep (rapid eye movement) similar eeg to awake
70
sleep stage progression
at beginning of night, more in SWS, later in night more in REM
71
REM sleep
brainstem ACh neurons are active, trigger eye movements but inhibit other motor output, body is relaxed ; overall stimulation of cerebral cortex producing EEG similar to waking
72
what is REM enhanced by
enhanced by drugs that activate ACh pathways (e.g. nicotine); bc of cholinergic nature of cortical activation during REM & the acetylcholinesterase inhibitors decrease the chemical breakdown of acetylcholine after release, increasing effect
73
what kind of animals exhibit REM
mammals and birds; it is not known in amphibians, reptiles, fish --> suggests recent evolutionary dev, related to brain complexity
74
babies and REM
in humans, babies spend a lot of time in REM sleep (~50% vs ~20% in adults)
75
REM and dreams
REM correlated w vivid dreaming which is likely related to robust cerebral cortical activity during REM
76
functions of sleep
Memory storage and consolidation (strengthening) of new learning is greatly improved by sleeping (majority of consolidation appears to take place during sleep)
Also, sleep “refreshes” brain so can learn new info
Deprivation of sleep triggered or exacerbates psychological problems
77
list of sleep problems
insomnia, apnea, narcolepsy, sleep paralysis, sleep walking, REM behavior disorder
78
insomnia
trouble sleeping
79
apnea
stopped breathing while sleeping which causes disrupted sleep
80
narcolepsy
non-restful NREM sleep, extreme daytime sleepiness caused by irregular sleep cycling between REM/NREM, associated with abnormalities related to orexin, a neuropeptide associated with maintaining wakefulness
81
sleep paralysis
partially awaken while in REM and feel paralyzed and hallucinating
82
REM behavior disorder
muscle movements intrude into REM --> flailing
83
in what stage does sleepwalking usually occur
NREM sleep (stages 3 and 4)
84
chronic sleep deficiency
biggest sleep related problem; leads to suboptimal performance, inc risk of accidents, probable long term adverse effects on health
85
what contributes to good sleep hygiene
```
pleasant sleep environment
avoiding stimulants late in the day
no alc close to bedtime
avoiding heavy food close to bedtime
avoiding bright screen devices before bedtime
daytime exercise, even if minimal
```
86
why can alcohol near bedtime be problematic
bc gets metabolized quickly in the body (~4 hours) so ppl wake up and cant go back to sleep
87
risks associated with pharmaceutical sleeping pills
can have very bad side effects like black out which is doing stuff that that u don't remember doing; also leads quickly to dependence
88
synesthesia
condition characterized by unusual blending of perceptions between different sensory modalities
89
what is more likely to be stored in long term memory
things that are emotional or significant, newer memories are more frail; undergo consolidation to become more stable
90
retrograde amnesia
inability to recall events from before the trauma
91
anterograde amnesia
more common, cant recall events after onset of amnesia
92
amnesia
pathological memory problems associated with injury or trauma
93
dementia
neurological condition characterized by global loss of cognitive abilities
94
vascular dementia
associated with accumulation of cell damaged related to impaired blood circulation
95
Alzheimer's
presence of senile plaques (extracellular deposits of polypeptide beta amylase) and neurofibrillary tangles (aggregates of tau protein, which stabilizes and assembles microtubules)
96
sedative hyp affect on memory
can produce temporary anterograde amnesia (blackout); heavy alc use can cause perm memory impairment
97
midazadam/Versed effect on memory
given to patients under partial anesthetization to impair persons ability to remember uncomfortable parts of the surgery
98
other drugs related to memory impairment
Cannabis, cholesterol-lowering drugs, opiods, older antihistamines; many of these are commonly used on elderly patients
99
nootropic
drugs claimed to improve cognition and memory, include caffeine, nicotine, meth
100
Hebb
suggested that networks of many neurons extending throughout cortex rep info stored in memory; large portions of brain work together to form memory
101
aplysia california
sea slug : retracts gills quickly when the siphon is touched; study by Kandel
trigger releases serotonin → activates GPCRs → cAMP → PKA → closing K+ leak channels → Ca 2+ opened longer → releases more NT
Studies indicate that up to ~1 hour after stimulus, faster response to same stimulus; if done multiple times last up to several days
Faster response is due to the serotonin activating more cAMP, which transcripts certain genes and elevates the NT responses
102
free running rhythm
Orgs will undergo circadian rhythm even if no environmental cues, but last slightly longer than 24 hours
103
Research fruitfly circadian rhythm
by researching PER: the suppression of PER transcription reduced PER production, which reduced PER suppression; 24 hr cycle
104
melanospin
the photosensitive (don't need rods/cones) ganglion cells that nerve axons connect to SCN
105
jet lag
when endogenous circadian rhythm doesn't match the environment
106
3 activities that human sleep studies measure
brain activity (w EEG), muscle movement, eye movement
107
NREM stages
divided into 4 stages with 4th being lowest freq of EEG activity
108
lucid dreaming
aware of dreaming while still asleep; goal of some spiritual traditions
109
what is mind
collection of mental states (thoughts, feelings, perceptions)
110
what do we think of as consciousness
awareness of self
111
mind body problem
how is mind related to physical processes in the brain and body
112
sentience
capacity to have experience of what it is like to be
113
feelings vs emotions
Feelings are the mental component of emotions; emotions= feeling +somatic qualities (changes in body, outward signs)
114
emotions vs mood
emotions are spontaneous, unbidden, and arise quickly whereas moods are usually more prolonged
115
why do we have feelings/emotions
social communication, provide for cooperative social systems
116
other aspects of emotion besides facial expression
changes in heart rate, blood pressure, skin temp, tone of voice, body pressure, hormone release
117
"Expression of Emotions in Man and Animals"
a book Darwin wrote about emotion, he studied facial expressions; he also said emotions not unique to humans
118
what NS is vagus nerve part of
parasympathetic NS
119
vagal tone
resting vagus nerve activity, relaxed emotional style;
characterized by:
- resilience when encountering neg emotions
- more freq experience of positive emotions
- greater prosocial expression
- improved physical health
120
electroceuticals
```
do vagus nerve stimulation externally
include TMS (transcranial magnetic stimulation), tDCS, tACS
```
121
thoughts vs feelings
thoughts have linguistic component (inner dialogue or describable images)
feelings - non linguistic and intuitive quality
122
Ekman
compared interpretation of facial expressions across different cultures
Evolution: basic emotions universal, even in sheltered communities
Constructivism: cultural factors “specify who can show emotion to whom & when”
123
primary function of facial expressions
communicate emotion to others
124
vagus nerve (aka CN 10)
elaborate connection between brain & large region of body’s core (including parasympathetic nerves: heart, lungs, etc); fiber consists of many axons, some myelinated, carry signals both directions, but >50% body → brain or afferent
125
afferent vs efferent
afferent : body --> brain
| efferent : brain --> body
126
amygdala
group of nuclei at base of temporal lobe heavily connected with sensory areas of cerebral cortex & brainstem neurons; involved w perception of emotional expressions (esp fear, anger); involved in signaling hypothalmus to start stress resp
127
hypothalamus and hormones
produces neuropeptide that regulates release of systemic hormones from nearby pituitary gland; releases oxytocin & vasopressin into blood as hormones;
Both O & V act at specific GCPRs when released into extracellular space w/in hypothalamus & cerebrospinal fluid to diffuse throughout CNS; axons also release into brainstem, hippocampus, amgdala; associated w/ prosocial actions (parental, trust, & cooperation)
128
adrenocorticotropic hormones
trigger adrenal glans to release cortisol, part of body response to stress/threat
129
oxytocin
works on female uterus during childbirth to induce contractions and stimulates production and release of milk
130
vasopressin
acts on kidneys to slow transfer of water from blood to urine
131
reward pathways
Olds discovered electrically stimulating certain brain regions in rats induced rats to execute behaviors to generate same stimulation
132
best known reward pathway
dopaminergic neurons in ventral tegmental area (pons) projecting to nuclear accumbens and medial prefontal cortex; highly complex and activates with enjoyable behaviors
133
serotonin
associated w mediation of positive mood; connection largely from neurochem of drugs used to treat mood disorders
134
depression
prolonged and dysfunctional dysphoric mood; malignant melancholy
135
how do clinical anti-dep meds like MAOIs and TCAs work
increase effect of norepinephrine and serotonin
136
MAOIs
monoamine oxidase inhibitors -inhibits enzyme deactivating norep, sero
137
TCA
tricyclic antidepressants - blocks/slows uptake of norep, sero
138
pro-social emotions
playful, love, gratitude; theorize most important in human behavior
139
mindfulness meditation
training & practice of bringing one’s awareness to a focus of attention; associated with manifestation of prosocial emotion & emotional balance
140
William James
Science of Mind
imp to study behavior--> psychology
imp to study biological underpinnings --> neuroscience
imp to study mental experience --> introspection, phenomenology (often hear this is subjective, "cant do science on it")
141
Rene Descartes and mind-body dualism
mind-body dualism --> try to understand body/nature as a kind of machine
142
George Berkeley and idealism
posited we don't know anthing except our own thoughts (idealism/mentalism)
143
speculations on why consciousness exists
→ emergent property of complex neurocircuitry, perhaps an epiphenomenon
→ evolution: awareness of experience produces adaptive advantage for survival?
→ is a fundamental property of the universe, along the lines of matter and energy
144
Cambridge Declaration of Consciousness
humans aint unique in possessing neurological substrates to generate consciousness
(deep brain structures assoc w emotion in humans are present in animals, animals also have similar pharmacological manipulations, problem solving, REM, etc)
145
mirror recognition
a test for self awareness if can recognize self in mirror
146
neural correlates of consciousness (NCC)
the way forward
→ continued neuroscientific investigations
→ subcellular molecular ordering
→ fundamental physics/biology/mind interface
→ powerful psychoactive drug effects
→ placebo effects
→ near death experiences/ dying and death
→ anomalous phenomena
→ refined introspection
147
paradigm shifts
Copernicus: Heliocentric Cosmos - sun center of things
Einstein : relativity of space and time
Quantum physics: wave particle duality, measurement and indeterminism
Darwin: biological evolution
Coming soon? Perhaps the biggest one so far abt mental experience and consciousness
148
reductionism
understanding living orgs thru framework of physical science (can it account for everything? also quantum is weird
149
quantum measurement problem
measuring changes system, Heisenberg uncertainty principle
150
SETI
search for extraterrestrial life
151
physicalism
describing reality thru physics; metaphysical framework of contemporary science
(requires explanations of mind, mental experience in terms of matter)
explanatory gap - difference between physical and subjective
