Term
| Are human & monkey cerebral hemispheres a lot alike or very different? |
|
Definition
|
|
Term
| Are there a lot or few cortical areas? |
|
Definition
|
|
Term
| Why do we use old world monkeys to understand human cognition? |
|
Definition
| they are remarkably close to us cognitively |
|
|
Term
| old world monkeys vs. new world monkeys |
|
Definition
| old world monkeys are more sorted for cognitive studies compared to new world monkeys because they are "smarter" |
|
|
Term
| ways in which rhesus macaques are like us/unlike us |
|
Definition
| about the size of a large dog, like us in regards that they have an opposable thumb, unlike us because they walk on all fours & have very sharp canines |
|
|
Term
| why are rhesus macaques suitable for studies in cognitive neuroscience? |
|
Definition
| they are by no means threatened! |
|
|
Term
| macaques & human brains look similar - although _____ |
|
Definition
| mass of brain relative to body is greater in humans |
|
|
Term
| which rodents have very convoluted brains? |
|
Definition
| capybara (by contrast to rats which have no folds!) |
|
|
Term
| why does brain get more convoluted as it gets larger? |
|
Definition
| conserve the surface-to-volume ratio |
|
|
Term
| two ways you could scale gray to white matter system up to a larger brain (BUT neither of these is what nature does!) |
|
Definition
1. conserve the ratio of gray matter volume to white matter volume
2. conserve cortical thickness |
|
|
Term
| how does nature scale gray to white matter in larger brains? |
|
Definition
| convoluted/folds allows nature to conserve the ratio of gray to white matter but also conserves cortical thickness |
|
|
Term
| are lobes about equivalent in macaque & human brains? |
|
Definition
|
|
Term
|
Definition
1. frontal
2. parietal
3. occipital
4. temporal |
|
|
Term
| how are lobes functionally distinguished? |
|
Definition
| damage to a certain lobe tends to cause a certain kind of impairment |
|
|
Term
| human brain vs. macaque: complexity of sulcal morphology |
|
Definition
| human brain has a much more complex & variable pattern at sulcal morphology |
|
|
Term
|
Definition
| anatomy of the cells that make up the cortex |
|
|
Term
| how were the first dyes used for staining neurons discovered? |
|
Definition
| came from the fashion craze for purple dresses! |
|
|
Term
| why do dyes work to stain neural bodies? |
|
Definition
| they had strong affinity for endoplasmic reticulum (which cell bodies are full of) & are basophilic |
|
|
Term
| what kind of cells are densely packed in layer 4 of primary visual cortex? |
|
Definition
|
|
Term
| layer 5 of primary motor cortex contains what kind of cells? |
|
Definition
|
|
Term
| average cell body is _____ microns in diameter |
|
Definition
|
|
Term
| neuroanatomists working in late 1800s discovered that the distribution of cells going down layers of cortex is not consistent --> allowed ______ |
|
Definition
| allowed the cortex to be divided into layers |
|
|
Term
| cortex layer 1 contains ______ |
|
Definition
| neuropil (extraordinarily little cell bodies) |
|
|
Term
| cortex layer 2 contains ______ |
|
Definition
|
|
Term
| cortex layer 3 contains _____ |
|
Definition
|
|
Term
| cortex layer 4 contains ______ |
|
Definition
|
|
Term
| cortex layer 5 contains ______ |
|
Definition
|
|
Term
| cortex layer 6 contains _____ |
|
Definition
| groups of pyramidal cells separated by fibers running through the cortex |
|
|
Term
| do different parts of cortex look the same? |
|
Definition
|
|
Term
| Brodmann mapped the hemisphere into areas (about 50) that are distinguished by ______ |
|
Definition
| patterns of cytoarchitecture |
|
|
Term
| do areas in Brodmann & von Economo systems coincide? |
|
Definition
|
|
Term
| why is studying inter-areal connectivity in the cerebral hemisphere important? |
|
Definition
| if we can understand how information is transmitted from area to area (connectional anatomy), this will greatly help us understand how the brain works |
|
|
Term
| original work to trace axons wanted to use a _______ method |
|
Definition
| degeneration; killing a cell body would cause axons to change/degenerate |
|
|
Term
| are corresponding loci in the left & right hemispheres interconnected? |
|
Definition
|
|
Term
| how are ascending connections from subcortical regions to cortex used for identifying cortical regions? |
|
Definition
| there are certain regions of cortex that are identifiable by connections with subcortical regions with a known function |
|
|
Term
| cortical connections are often organized _______ |
|
Definition
|
|
Term
| 3 main brain regions for vision |
|
Definition
1. retina
2. lateral geniculate nucleus
3. primary visual cortex |
|
|
Term
| 6 main brain regions for hearing |
|
Definition
1. cochlea
2. cochlear nucleus
3. superior olive
4. inferior colliculus
5. medial geniculate nucleus
6. primary auditory cortex |
|
|
Term
| 4 main brain regions for touch |
|
Definition
1. spinal ganglion
2. dorsal column nuclei
3. ventrolateral nucleus
4. primary somesthetic cortex |
|
|
Term
| 6 main brain regions for movement |
|
Definition
1. spinal cord
2. cerebellum
3. various brainstem nuclei
4. ventrolateral nucleus
5. basal ganglia
6. motor cortex |
|
|
Term
| 8 main brain regions for viscero-homeostatic function |
|
Definition
1. visceral sensory ganglia
2. visceral sensory nuclei
3. hypothalamus
4. autonomic ganglia
5. blood
6. visceral motor nuclei
7. amygdala
8. orbitofrontal cortex |
|
|
Term
| why are association cortices called "association"? |
|
Definition
| they put together information from the surrounding areas with neatly specified functions to form associations with what is going on in different areas |
|
|
Term
| how is the limbic system situated in the brain? |
|
Definition
| kind of surrounds other cortices if you take a flattened-out view of the brain |
|
|
Term
| how are well-defined cortices (visual, auditory, somato, motor) arranged relative to association cortices? |
|
Definition
| they kind of sit "within a sea" of association cortices if you take a flattened-out view of the brain |
|
|
Term
| what is important about prefrontal cortex projecting back out to motor cortex but also getting input from orbitofrontal cortex? |
|
Definition
| allow emotion to have a role in motor output |
|
|
Term
| what differentiates human brains from monkey brains? |
|
Definition
| humans have much more vast association domains! |
|
|
Term
| how do lower order areas compare to higher order areas in terms of composition of brain hemisphere in humans? |
|
Definition
|
|
Term
| 2 regions that exhibit the greatest degree of expansion in humans |
|
Definition
1. parietotemporal association cortex
2. frontal association cortex |
|
|
Term
| what was the inspiration for the Barber's Diamond illusion? |
|
Definition
| illusion created by old fashioned barber's poles where the stripes rotate & look like they can go either up or down |
|
|
Term
| Barber's Diamond illusion |
|
Definition
| stripes moving to the left in a diamond are moving straight, uniformly to the left; depending on the depth perception of the diamonds around the center striped diamond make the stripes look either like they are moving up & to the left or down & to the left |
|
|
Term
|
Definition
| if you stand looking at a waterfall for a period of minutes & then you look at a rock, the flecks in the granite will look like they appear to drift up (opposite actual movement of the waterfall) |
|
|
Term
| what is important to keep in mind when looking at flattened-out views of the cortex? |
|
Definition
| the cortex has an intrinsic curvature, so if you flatten it out you do lose some information in how things are spatially connected |
|
|
Term
| receptive field of neurons in area V1 |
|
Definition
| each neuron has a small receptive field (a degree or at most a couple of degrees in diameter) --> it responds to visual events only in a tiny part of the visual field |
|
|
Term
| how do receptive fields change as you move farther out from V1 in visual field hierarchy? |
|
Definition
| the mapping of the visual field becomes cruder & cruder (receptive fields become larger & larger) |
|
|
Term
| Ungerleider's discovery regarding V1 streams of information |
|
Definition
| there was not only an anatomical split between dorsal & ventral streams, but they serve distinct functions too! |
|
|
Term
| MT gets input from ______ & projects out to ______ |
|
Definition
| primary visual areas (V1-V4); parietal cortex association areas |
|
|
Term
| MT was discovered in the 1970s via _______ |
|
Definition
| mapping studies in monkeys |
|
|
Term
|
Definition
| dorsal stream, parietal lobe |
|
|
Term
|
Definition
| ventral stream, temporal lobe |
|
|
Term
| motion vision depends on ______ |
|
Definition
| area MT (MT is housed in the dorsal stream) |
|
|
Term
| 3 symptoms of a woman with problems in area MT |
|
Definition
1. unable to perceive the movement in a cup when the fluid rose
2. could not see the movements of the mouth of the speaker
3. unable to cross the street because she could not judge a car's velocity |
|
|
Term
| examples of visual functions that are normal following temporal lobe injury |
|
Definition
| visual ability, stereopsis, color vision, recognition, reading, saccadic localization, tactile motion |
|
|
Term
| 3 visual things that can be impaired following temporal lobe injury |
|
Definition
1. motion detection
2. direction discrimination
3. motion aftereffect |
|
|
Term
|
Definition
| specific issues with motion vision while other vision is preserved (observed in a patient with damage to middle temporal gyrus) |
|
|
Term
| color/direction selectivity in areas MT vs. V4/TE |
|
Definition
MT = direction but basically no color information
V4/TE = color but basically no direction information |
|
|
Term
| ventral stream vs. dorsal stream in terms of sensitivity to color & motion |
|
Definition
| ventral stream areas (V4 & TE) are sensitive to color whereas dorsal stream area (MT) is sensitive to motion; fits with the idea that they serve recognition & spatial vision |
|
|
Term
| what can be gained by having stimuli presented in different positions? |
|
Definition
| allowed authors to discover receptive fields of specific neurons |
|
|
Term
| 2 important thins to remember when doing a recording study |
|
Definition
1. neurons have spontaneous activity!
2. neurons fire stochastically |
|
|
Term
| if a neuron is directionally selective, how will its firing change throughout stimulus presentation? |
|
Definition
| you will see/hear it firing strongest for a specific direction, no change from baseline for others, & on others still go completely silent (often this is the case for opposite direction from preferred direction) |
|
|
Term
|
Definition
| described neurons in rabbit retina selective for direction of motion & proposed a simple model to account for the phenotype |
|
|
Term
| model describing direction selectivity in retina |
|
Definition
| if you have point A that has a 4 ms delay to neuron X & point B that has a 1 ms delay to neuron X --> when something moves from point A to point B, neuron X will get those two signals simultaneously & respond to movement in that direction! |
|
|
Term
| who first demonstrated the relationship between neural activity in MT & motion vision? |
|
Definition
|
|
Term
| Newsome's task for studying motion vision |
|
Definition
while the monkey looks at a fixation point, a moving dot display with some degree of coherence is presented in the neuron's receptive field; the monkey must make an eye movement to the target toward which he thinks the motion flowed
motion of the dots could flow with 100% coherence OR there could be various degrees of noise (random moving dots) |
|
|
Term
| Newsome motion vision task results |
|
Definition
| monkey performance resulted in a psychometric curve for the % coherence necessary to reach a certain percent correct |
|
|
Term
| how do MT neurons in monkey compare to performance in terms of indicating direction of motion when viewing a stimulus? |
|
Definition
| MT neurons in the monkey are similar with regards to how their performance degrades as coherence degrades (just like behavior performance degrades as coherence degrades) |
|
|
Term
| results of Newsome's experiment studying correlation between MT neural activity & behavior performance of motion dot moving stimuli |
|
Definition
| there is a correlation between MT firing & choice; example: when there is no correlated motion & the monkey must guess, neuronal activity in MT is correlated with his guesses |
|
|
Term
| Newsome experiment to demonstrate the sufficiency of MT firing for direction choice results |
|
Definition
| electrical stimulation of a site in MT where neurons respond to motion in a certain direction sways the monkey's perception towards that direction |
|
|
Term
| Newsome experiment to demonstrate the sufficiency of MT firing for direction choice |
|
Definition
| he would have the motion going towards one point & stimulate MT neurons for a separate point --> monkey would end up making a saccade to a point in the middle between the two |
|
|
Term
| is MT stimulation sufficient to drive motion perception by the monkey? |
|
Definition
| yes (particularly at low coherence) |
|
|
Term
| lesions of area MT in the monkey produce an impairment of ______ |
|
Definition
|
|
Term
| comparison of coherence threshold required to determine dot movement in control monkeys vs. monkeys with lesioned MT |
|
Definition
| significantly increased coherence threshold required in lesioned monkeys! |
|
|
Term
| does lesion of area MT in monkeys affect other information about shapes (besides motion)? |
|
Definition
|
|
Term
| interesting result of Newsome's MT lesion experiments regarding impaired motion vision |
|
Definition
| effects were not persistent --> if he waited weeks & then re-tested the monkey, they would get better at the task |
|
|
Term
| how do neurons in area MT relate to our perception of the Barber's diamond illusion? |
|
Definition
| neuron representing bars moving to the right can shift their firing as context changes to be stronger for either up & to the right or down & to the right (just like how our perception of the stripes changes as the background around the middle diamond changes) |
|
|
Term
| conclusions made from studying if MT neurons experience barber's diamond illusion like how we perceive it |
|
Definition
| neurons in MT experience the barber's diamond illusion EVEN THOUGH the context information that change our perception are outside of the receptive field of the neuron |
|
|
Term
| how was the study done to determine if MT neurons experience barber's diamond illusion like how we perceive it? |
|
Definition
| recording from cells in monkeys |
|
|
Term
| how was the study done to determine if MT neurons experience the motion aftereffect illusion like how we perceive it? |
|
Definition
|
|
Term
| Tootell et al study regarding MT neurons experiencing motion aftereffect illusion conclusion |
|
Definition
| the BOLD response to a moving stimulus greatly exceeds the response to a stationary stimulus in MT but not V1 of humans |
|
|
Term
| how was it determined that MT neurons experience motion aftereffect illusion like how we perceive it? |
|
Definition
| the BOLD "after signal" in MT closely parallels, in the time course of its fall-off, the decay of the motion aftereffect as measured in psychophysical experiments |
|
|
Term
| what disorder allows patients to look at an image & copy it, but if they are asked what it is, they cannot name the object? |
|
Definition
|
|
Term
| visual object agnosia results in impaired _______ |
|
Definition
| recognition (however there is no indication of issues with visual competence) |
|
|
Term
| examples of impairments in prosopagnosia |
|
Definition
| recognize acquaintances or family members, recognize themselves in mirrors, recognize famous individuals in photographs, etc. |
|
|
Term
|
Definition
| a deficit of facial recognition specifically |
|
|
Term
| how can patients with prosopagnosia compensate? |
|
Definition
| recognize people from their voices, recognize people from distinctive hairstyles/glasses/etc. |
|
|
Term
| is prosopagnosia congenital? |
|
Definition
|
|
Term
| visual object agnosia typically arises from bilateral damage to ______ & ______ |
|
Definition
|
|
Term
| prosopagnosia typically arises from right hemisphere damage to ______ |
|
Definition
|
|
Term
| fMRI data has demonstrated that visual object recognition "lights up" the _______ & ______ gyri; facial recognition "lights up" the _______ |
|
Definition
| fusiform & lingual; fusiform |
|
|
Term
| damage to parahippocampal gyrus, fusiform gyrus, lingual gyrus typically involves _______ |
|
Definition
|
|
Term
| damage to parahippocampal place area (PPA) (near parahippocampal gyrus) results in _______ |
|
Definition
| topographic amnesia (inability to recognize places) |
|
|
Term
| damage to visual word form area (VWFA) (near fusiform gyrus in left hemisphere) results in ______ |
|
Definition
| pure alexia (reading printed words is affected but spelling/writing are not) |
|
|
Term
| activation of area LO vs. area V1 |
|
Definition
| area LO was more strongly activated when objects/faces were shown to the individuals compared to area V1 which was more strongly activated when textures were shown |
|
|
Term
| other name for fusiform gyrus |
|
Definition
|
|
Term
| what area is more strongly activated by faces compared to common objects (especially in the right hemisphere!) |
|
Definition
|
|
Term
| Holmes & Gross experiment to demonstrate importance of IT in visual object agnosia |
|
Definition
| monkeys had to learn between two objects which represented "good" to get a reward; monkeys without IT were unable to perform the task |
|
|
Term
| results of Holmes & Gross experiment studying role of IT in visual object agnosia...could monkeys re-learn a "good" vs. a "bad" object? |
|
Definition
| following the lesions, monkeys could re-learn the task with new objects, but it took a lot longer compared to control monkeys |
|
|
Term
| how do the responses to IT neurons that respond to hands change for actual hands vs. drawn outlines of hands? |
|
Definition
| responded the most strongly for actual hands & less strongly for just drawn outlines of hands |
|
|
Term
| All IT neurons have some form of ______ selectivity in their responses |
|
Definition
| image; each one will respond to a certain set of images & not to others |
|
|
Term
| IT neurons respond selectively to complex images with a degree of _______ invariance |
|
Definition
|
|
Term
| how was it discovered that IT neurons have location invariance? |
|
Definition
| authors presented images in various locations (center, left, right, upper, lower) & you could see some location selectivity, but for the most part, the object that elicited the greatest response would elicit the greatest response compared to other objects regardless of the location |
|
|
Term
| how is scale invariance represented in IT neurons? |
|
Definition
| ideal object does not change compared to other objects regardless of the size of that object |
|
|
Term
| results of authors presenting an ideal image to the IT neurons in different orientations |
|
Definition
| found that the other orientations elicited essentially no response from IT neurons that like it in the original orientation! |
|
|
Term
| Tanaka et al study finding the minimal combination of features required for driving an IT neuron |
|
Definition
| would show a monkey various objects until he found one that elicited a good response for the neuron of interest --> would simplify the object down to a 2D drawing representation & try to find a 2D representation that still elicited a strong response from the cell --> keep simplifying the image down until there was no more response from the cell |
|
|
Term
| conclusion from Tanaka et al study to find the minimal combination of features required for driving an IT neuron |
|
Definition
| neuron sin IT represent complex attributes of images (NOT specific objects!) so that any given object can contain attributes that excite multiple neurons |
|
|
Term
| how is the representation of images in IT distributed & continuous? |
|
Definition
| if each IT neuron represents a partial feature potentially present in many images (as suggested by Tanaka) & if each neuron fires in proportion to how closely the content of the current image matches its partial feature, then the representation of images in IT is distributed (each image is represented by the activity of a great many neurons) & continuous (it matters not which neurons are active but how much each neuron is active) |
|
|
Term
| how are images in the same category (i.e. "face" or "car") represented in IT neuronal activation space? |
|
Definition
| due to similarities in activation patterns, similar things cluster together! |
|
|
Term
| "disentanglement" (Jim DeCarlo) |
|
Definition
| as one goes up the ventral stream hierarchy, the points representing the objects in different categories move farther & farther apart so they become linearly dissociable |
|
|
Term
| oddball search study (Sripati & Olson) |
|
Definition
| the ability of monkey IT neurons to tell two images apart (measured as the average, across a large neuronal population, of the difference in firing rate elicited by the two images) is strongly correlated with the ability of humans to tell the images apart (measured as the speed with which they can find one embedded in a field of the others) |
|
|
Term
| how are images that are hard to tell apart for each other by humans related in IT activation space? |
|
Definition
|
|
Term
| Agrawal, Hari, Arun study about learning a script & oddball search |
|
Definition
| if you can read a language, you can more easily distinguish between two similar letters & perform the oddball search more quickly AND they moved apart in activation space in IT neurons |
|
|
Term
| binocular rivalry, when subjects "fuse" two images together (one seen through the right & one through the left eye) --> you see ______ |
|
Definition
| alternating representations of the two different images |
|
|
Term
| if I put a microelectrode in "face cortex" & I electrically stimulate those neurons --> ? |
|
Definition
| I can get a monkey to "perceive" faces & report that this is what he is seeing |
|
|
Term
| Afraz et al study: in monkeys performing a task requiring them to report with an eye movement (rightward or leftward) whether a foveally presented image represented a face or non-face object, electrical stimulation of patches of face cells in IT --> ? |
|
Definition
| induced a bias to report that the image represented a face |
|
|
Term
|
Definition
| travelling pressure waves through a medium |
|
|
Term
| humans' sensitivity to oscillations in range ______ Hz (sound) (Hz = cycles per second) |
|
Definition
|
|
Term
| how can beating sinusoids reinforce or cancel sound depending on instantaneous values? |
|
Definition
if sounds are happening that are close in frequency, they can sum together to cause a new waveform
if the two sound waves are out of sync, then they can sum to 0 & the wave will flatten out |
|
|
Term
|
Definition
| interactions between the wave forms |
|
|
Term
| larger the difference between the frequencies of two sounds --> summing together sounds ______ |
|
Definition
| less like a pure tone (with amplitude modulation) & sounds kind of fluttery --> even more different you hear a chord! |
|
|
Term
| different parts of the cochlea respond to different ______ |
|
Definition
|
|
Term
| sound first hits the outer ear --> gets into the ______ |
|
Definition
|
|
Term
| _____ vibrates with response to sound |
|
Definition
| tympanic membrane (ear drum) |
|
|
Term
| 3 tiny bones that get the sound into the cochlea |
|
Definition
1. middle ear stapes
2. incus
3. malleus |
|
|
Term
| cochlea itself is embedded in ______ |
|
Definition
|
|
Term
| coils at the top of cochlea are part of ______ system |
|
Definition
| vestibular balance (operate separately from hearing system) |
|
|
Term
| where does electrical activity for hearing really start happening? |
|
Definition
| a bundle of nerves that come out of the cochlea (auditory nerve) |
|
|
Term
| 5 steps for transduction of sound |
|
Definition
1. sound hits the outer ear
2. propagates through the inner ear to the tympanic membrane
3. oscillates to cause the stapes to oscillate
4. oscillates the cochlea
5. gets transduced into sounds |
|
|
Term
| what is the implication of hair cells being in an environment so full of potassium? |
|
Definition
| any time it gets stimulated it can depolarize |
|
|
Term
| what causes hair cells to fire? |
|
Definition
| movement of stereo-cilia causes opening of hair cells |
|
|
Term
| oscillation of basilar membrane --> ? |
|
Definition
| causes shearing movement on stereocilia of hair cells |
|
|
Term
| we have ______ rows of outer hair cells |
|
Definition
|
|
Term
| we have _______ rows of inner hair cells |
|
Definition
|
|
Term
| do all rows of hair cells have stereocilia? |
|
Definition
|
|
Term
| ______ opens potassium channels in stereocilia |
|
Definition
|
|
Term
| how is motion important for hair cell electrochemistry? |
|
Definition
| motion in one direction opens ion gates; motion in other direction closes ion gates |
|
|
Term
| ______ opens & shuts ion channels on hair cells |
|
Definition
|
|
Term
| how many neurons are in the human auditory nerve (8th nerve)? |
|
Definition
|
|
Term
| is the human auditory nerve primarily afferent or efferent? |
|
Definition
|
|
Term
| do IHCs & OHCs project to the same or different places? |
|
Definition
|
|
Term
| ascending information for hearing is primarily conveyed by ______ |
|
Definition
|
|
Term
| descending information: where it hits IHC vs. OHC |
|
Definition
IHC: descending information connects onto its afferent connections to brain
OHC: descending information connects directly onto OHC body |
|
|
Term
| is efferent information for hearing more connected to OHCs or IHCs? |
|
Definition
|
|
Term
| where are high vs. low frequencies affecting the BM displacement in the cochlea? |
|
Definition
high frequencies more basal (oval window)
low frequencies apical (helicotrema) |
|
|
Term
| cochlear mechanics are primarily dependent upon ______ |
|
Definition
|
|
Term
| how does sound travel through the cochlea? |
|
Definition
| get a wave that travels from base to apex |
|
|
Term
| some clues that cochlear amplification is an active process |
|
Definition
| responses nonlinear, tuning too sharp to be passive, Von Bekesy found broad peaks in cadavers, later researchers found sharper peaks, tuning at AN sharp, damaged OHCs results in flat tuning, drugs can induce flatter tuning, OHCs change shape with activity, otoacoustic emissions, etc. |
|
|
Term
| OHC or IHC changes length/width with electrochemical stimulation? |
|
Definition
|
|
Term
| PRESTIN (found in OHC [but not inner]) |
|
Definition
| protein that allows for the motility of outer hair cells |
|
|
Term
| firing rate of the 8th nerve is intricately linked with ______ |
|
Definition
| hyperpolarization & depolarization of hair cells |
|
|
Term
| depolarization of hair cells --> what change in firing rate of the 8th nerve? |
|
Definition
|
|
Term
| hyperpolarization of hair cells --> what change in firing rate of the 8th nerve? |
|
Definition
|
|
Term
| 3 things that cell polarization & thus auditory nerve firing pattern depend on |
|
Definition
1. place along cochlea (cochlear mechanics perform Fourier analysis)
2. amount of acoustic energy (nonlinear, compressive growth response)
3. frequency of stimulation (AC/DC components) |
|
|
Term
| neurons have ______ dB dynamic range |
|
Definition
|
|
Term
|
Definition
| the dB level at which the firing rate of an auditory nerve begins to change |
|
|
Term
| do different nerve fibers have the same or different shapes of tuning curves? |
|
Definition
|
|
Term
| to hear high intensity sound levels/fluctuations --> more important to have high or medium/low spontaneous firing rate nerve fibers? |
|
Definition
|
|
Term
| hearing low intensity sound levels/fluctuations --> more important to have high or medium/low spontaneous firing rate nerve fibers? |
|
Definition
|
|
Term
| noise exposure preferentially damages ______ spontaneous firing rate fibers |
|
Definition
|
|
Term
| what do you do to solve mechanical transduction loss (destruction of middle ear bones)? |
|
Definition
| amplify the sound levels that get into the inner ear (easy to fix!) |
|
|
Term
| what happens if there is damage to the OHCs? |
|
Definition
| you lose amplification that you would normally get at higher frequency sounds |
|
|
Term
| if OHCs are damaged that are specific for a certain frequency --> ? |
|
Definition
| you can lose hearing at that frequency specifically |
|
|
Term
| does a lot or a little auditory processing happen before getting to cortex? |
|
Definition
|
|
Term
| are ascending or descending auditory pathways better understood? |
|
Definition
|
|
Term
| what is the main role for descending auditory pathways? |
|
Definition
| automatic gain control of middle ear |
|
|
Term
| in the auditory nerve, parallel fibers convey ______ information |
|
Definition
|
|
Term
| is there a tonotopic gradient of tuning at the cochlear nucleus? |
|
Definition
|
|
Term
| 3 distinct regions that have distinct processing in cochlear nucleus (CN) |
|
Definition
1. dorsal
2. anteroventral
3. posteroventral |
|
|
Term
| 2 typical approaches to classification of CN neurons |
|
Definition
|
|
Term
| main cell type in dorsal CN |
|
Definition
|
|
Term
| 3 main cell types in posteroventral CN |
|
Definition
1. octopus
2. stellate
3. bushy |
|
|
Term
| 2 main cell types in anteroventral CN |
|
Definition
|
|
Term
| ______ tend to get inputs that are very localized in the frequency areas that they like |
|
Definition
|
|
Term
| ________ traverse a huge number of frequency regions |
|
Definition
|
|
Term
| _______ have extraordinarily complex local circuit connection that interact with all sorts of other cells in that region |
|
Definition
|
|
Term
| function of octopus cells found in PVCN |
|
Definition
| onset detection across frequency |
|
|
Term
| physiology of octopus cells found in PVCN |
|
Definition
| respond to broadband inputs well, not narrowband; respond at onset (or on each cycle) |
|
|
Term
| do octopus cells have broad or sharp tuning curves? |
|
Definition
| broad (esp. at threshold), often flat about 2 kHz |
|
|
Term
| do octopus cells like broadband or narrowband input? |
|
Definition
|
|
Term
| when to octopus cells fire? |
|
Definition
| only at onset to tones (single spikes) |
|
|
Term
| function of spherical & globular bushy cells in the AVCN |
|
Definition
| fine timing & phase locking |
|
|
Term
| physiology of spherical & globular bushy cells in the AVCN |
|
Definition
| extremely high precise phase locking --> better than ANF; frequency tuning like ANF |
|
|
Term
| specializations of spherical & globular bushy cells in the AVCN |
|
Definition
| multiple inputs, none extraordinarily strong |
|
|
Term
| despite having remarkably similar neural dynamics, how are the inputs to octopus vs. bushy cells different? |
|
Definition
| octopus = across frequencies; bushy = within frequency |
|
|
Term
| function of fusiform cells in DCN |
|
Definition
|
|
Term
| describe the primary output cell of the DCN circuit model |
|
Definition
| excited by a narrow range of frequencies; is inhibited by a cell that is tuned to a slightly different frequency |
|
|
Term
| 3 steps in ascending auditory pathway |
|
Definition
1. cochlea
2. CN
3. contralateral & ipsilateral superior olivary complex |
|
|
Term
| 3 places spherical bushy cells project to |
|
Definition
1. ipsilateral MSO
2. contralateral MSO
3. ipsilateral LSO |
|
|
Term
| projection of globular bushy cells |
|
Definition
| contralateral MNTB (medium nucleus of the trapezoid body) --> large synapse to LSO |
|
|
Term
| are bushy cells temporally precise? |
|
Definition
|
|
Term
| LSO output is driven by relative input from ______ |
|
Definition
|
|
Term
| Jeffress model of MSO coincidence detection |
|
Definition
| cells respond when they get input from left & right at the same time |
|
|
Term
| ______ are good for interaural time difference temporal coincidence detector cells |
|
Definition
|
|
Term
| 2 ways LSO is different from MSO |
|
Definition
1. inverted input
2. response to envelope rather than fine-time, cycle-by-cycle phase |
|
|
Term
|
Definition
1. excitation from ipsilateral bushy cell
2. inhibition from the MNTB (which is innervated by contralateral bushy cell) |
|
|
Term
| what is the first thing to go with hearing issues? |
|
Definition
| selective hearing (think: cocktail party problem!) |
|
|
Term
| is selective attention harder for auditory system or vision? |
|
Definition
|
|
Term
| does the brain store the content of unattended sounds? |
|
Definition
|
|
Term
| are distinct features of auditory information processed in the same or different areas of the temporal lobe? |
|
Definition
|
|
Term
| Brodbeck et al experiment regarding the attention effect with hearing |
|
Definition
| overlapping voices cause both acoustic information to be taken in (i.e. a male or female voice) BUT the parts of the temporal lobe that encode content information only light up for the voice to which you were paying attention |
|
|
Term
|
Definition
subjects maintain fixation on a spot on a screen while a cue & then a target is presented --> target is difficult to see & when it appears the subject must press a lever indicating direction
in 70-85% of trials, the cue indicates the side of the screen on which the target will appear; in 150-30% of the trials, the cue does not indicate the side of the screen on which the target will appear |
|
|
Term
| the Posner paradigm has been widely used for studies of ______ |
|
Definition
| covert orienting of attention |
|
|
Term
| results of the Posner task |
|
Definition
valid cues --> decreased reaction times
invalid cues --> increased reaction times |
|
|
Term
| Cheal & Lynn adaptation of the Posner task |
|
Definition
| on some trials, the cues were in the location of the "T"; on other trials, the cue was an arrow in the middle pointing to the side of the screen to which the "T" would appear |
|
|
Term
| results of the Cheal & Lynn adaptation of the Posner task |
|
Definition
| the performance following the presentation of a cue in the position of the "T" was very fast; the performance following the presentation of the arrow cue was not as rapid but we saw a greater difference between first block of trials to last block of trials |
|
|
Term
| Juola et al adaptation of the Posner task: asking how performance depends on whether the arrow cue was valid and/or the peripheral onset cue was valid |
|
Definition
on every trial there were two cues: a central arrow & a peripheral onset cue
on any given trial, both cues could be valid/only arrow could be valid/only peripheral onset cue could be valid/neither could be valid |
|
|
Term
| why did Juola et al include a probability factor in how often a periphery or arrow cue was correct in any given scenario on their task? |
|
Definition
| made it probabilistic because the individual would have to decide to pay attention to one of the factors (it was decision because it was still not a 100% given) |
|
|
Term
| Juola et al results: "neither" scenario (arrow correct 25%; periphery correct 25%) |
|
Definition
| slight improvement of reaction time when both arrow & periphery were correct & also when onset was correct |
|
|
Term
| Juola et al results: "onset" scenario (arrow correct 25%; periphery correct 75%) |
|
Definition
| huge improvement of reaction time when onset alone was correct & when both were correct; arrow cue alone being correct is just as long of a RT as when neither correct |
|
|
Term
| Juola et al results: "arrow" scenario (arrow correct 75%; periphery correct 25%) |
|
Definition
| either onset cue or arrow cue being valid is just about equal in terms of how they decrease RT (both are reduced from when neither are valid) |
|
|
Term
| Juola et al results: "both" scenario (arrow correct 75%; periphery correct 75%) |
|
Definition
| only the onset cue appears to be helpful! |
|
|
Term
| overall conclusion of Juola et al Posner task adaptation (arrow & periphery cue) |
|
Definition
| it is possible for cues indicating where a stimulus is going to appear to control attention to that stimulus with consequent improvement in performance in either detection or discrimination |
|
|
Term
| does attention have an effect on visual responsiveness in visual cortex? |
|
Definition
|
|
Term
| De Yon et al study results: used a stimulus in which gratings of various orientations moving in various directions appear in entire visual field but subject was instructed about the area to which they should attend |
|
Definition
| under these circumstances (visual stimulation constant but attention shifting), they saw that as attention moved, the zone of strongest activation moved |
|
|
Term
| conclusion from De Yon et al study of V1 |
|
Definition
| V1 shows both visual retinotopy & attentional retinotopy |
|
|
Term
| Mansell et al results: had monkey maintain fixation after having plotted out receptive fields of neurons in MT --> stimulated with dots moving in two opposite directions simultaneously --> monkey was instructed to attend to either left dot or right dot |
|
Definition
if a monkey was attending to left dot (for example): a neuron may fire much more strongly during time 1 (dot moving down) compared to time 2 (dot moving up)
saw the reverse when the monkey was instructed to attend to the right dot (up during time 1 & down during time 2) --> saw the reverse pattern of activation! |
|
|
Term
| in MT when multiple stimuli are present in the visual field & monkey attends to one of them, the firing of the neuron goes along with ______ |
|
Definition
| the motion of the stimulus being attended to |
|
|
Term
| Chelazzi et al results (monkey maintains fixation --> a sample image appears at fixation point --> goes back to fixation dot --> two images appear in the periphery (one matches sample & the other doesn't) --> monkey must saccade to image that matched the one that initially appeared (all of this one while recording form IT!)): at initial showing of sample |
|
Definition
| neuron would respond more strongly to its preferred image (i.e. if it preferred a flower over a coffee cup) |
|
|
Term
| Chelazzi et al results (monkey maintains fixation --> a sample image appears at fixation point --> goes back to fixation dot --> two images appear in the periphery (one matches sample & the other doesn't) --> monkey must saccade to image that matched the one that initially appeared (all of this one while recording form IT!)): when back to fixation point |
|
Definition
| a neuron's baseline would be a little higher if its preferred image was previously shown |
|
|
Term
| Chelazzi et al results (monkey maintains fixation --> a sample image appears at fixation point --> goes back to fixation dot --> two images appear in the periphery (one matches sample & the other doesn't) --> monkey must saccade to image that matched the one that initially appeared (all of this one while recording form IT!)): when two images pop up |
|
Definition
| firing overall IT neurons shoot up & stays high (or may increase) when monkey is making a movement to that preferred object |
|
|
Term
| Chelazzi et al results (monkey maintains fixation --> a sample image appears at fixation point --> goes back to fixation dot --> two images appear in the periphery (one matches sample & the other doesn't) --> monkey must saccade to image that matched the one that initially appeared (all of this one while recording form IT!)): conclusion overall |
|
Definition
| images to which the monkey is paying attention dominates the activity of neurons by eliciting a strong response (firing rate effect!) |
|
|
Term
| Cohen et al results regarding attention & noise correlation in V4 |
|
Definition
| attention reduces noise correlation --> when neurons are task-engaged, they become less susceptible to generalized noise signals |
|
|
Term
| Desimone et al results: recording from V4 for spike rates/LFP when monkey is attending outside of receptive field |
|
Definition
| little periodicity in LFP, little periodicity in spikes fired by neurons |
|
|
Term
| Desimone et al results: recording from V4 for spike rates/LFP when monkey is attending inside of receptive field |
|
Definition
| you see periodicity in LFP & the spiking of the neurons |
|
|
Term
| in the Desimone et al study on visual attention, do they use the same or different stimuli? |
|
Definition
| STIMULI ARE THE SAME! the only thing that changes is the monkey's attention |
|
|
Term
| why might performance benefit from the spiking/LFP periodicity seen when attention is payed to something in the neural receptive field |
|
Definition
| if neurons in V4 are responding to stimulus in attended location fire in frequency at gamma frequency --> spikes will hit neurons downstream in target cortices more strongly/keep the postsynaptic responses in line |
|
|
Term
| Corbetta study that gave rise to the premotor theory of attention |
|
Definition
| studying human brain scans when they either made eye movements or underwent covert attention (not making eye movements) --> there was a large degree of overlap in eye movement & attention-related zones in parietal & frontal cortices |
|
|
Term
| Russo & Bruce: how did the eye's starting point affect the direction/amplitude of the saccade caused by stimulation of FEF? |
|
Definition
| the direction & amplitude of the saccade tend to be constant at a given site regardless of the eye's starting point |
|
|
Term
|
Definition
| monkey fixates on center of screen --> cue appears in periphery --> delay period during which monkey must fixate on center --> monkey then makes eye movement to location where the cue was present to get reward |
|
|
Term
| Thompson et al lever-search task |
|
Definition
| recorded from FEF neurons while monkeys maintain central fixation --> array of 8 images appears in a circle around center point in periphery --> 7 are "O" & 1 is a "C" --> monkey must move a lever to indicate which direction the gap in the "C" is facing WITHOUT making an eye movement |
|
|
Term
| Robinson et al results (trained monkeys to perform a Posner task with peripheral cues & also with central symbolic arrow cues --> on any given trial, one of the two cues would appear --> a target would be presented after a brief delay) |
|
Definition
| monkey showed clear benefit in finding target after valid cues even when they were prevented from making eye movements to that area |
|
|
Term
| when monkeys shift attention covertly, they also program ______ |
|
Definition
| eye movements to the attended location |
|
|
Term
| Moore et al results (electrically stimulated the monkey FEF at currents so low that they did not elicit eye movements) |
|
Definition
| attention still shifted in the direction the eyes would have moved as reflected by a decrease in brightness threshold for detection of a small spot flashed in a field of distractors |
|
|
Term
| clinical test for neglect: cancellation task |
|
Definition
| patient is given a piece of paper with a bunch of symbols & asked to circle symbols of a given type |
|
|
Term
| clinical test for neglect: line bisection |
|
Definition
| patient is given a piece of paper & a pencil; on the paper is drawn a line with the left & right edges mark; patient is asked to draw a line that bisects the line through its center |
|
|
Term
| clinical test for neglect: copying |
|
Definition
| patient is asked to draw copies of images (e.g. clock, house, flower, etc.) |
|
|
Term
| the locus most often associated with neglect in humans is the _______ |
|
Definition
| inferior parietal cortex (BA 39,40) of the right hemisphere |
|
|
Term
| right-sided lesion of inferior parietal cortex --> ? |
|
Definition
|
|
Term
| take a bunch of patients with left hemi-spatial neglect & superimpose their lesions, what is common of their lesions? |
|
Definition
| lateral parietal territory |
|
|
Term
| why right hemisphere more than left hemisphere for neglect? |
|
Definition
| probably because language is typically lateralized to the left hemisphere in humans & attentional functions have been displaced into the right hemisphere as language-related processes took residence in the left hemisphere |
|
|
Term
| study: took a cohort of left-handed people, in some of whom language was lateralized to the right hemisphere & in some of whom language was lateralized to the left hemisphere --> had these people perform a covert spatial attention task |
|
Definition
| in those with left hemisphere language functions, activation of right parietal cortex was stronger than activation of left parietal cortex (the opposite was true for those with right hemisphere language lateralization) |
|
|
Term
| is hemispatial neglect limited to visual functions? |
|
Definition
|
|
Term
| 4 similar symptoms that often accompany neglect |
|
Definition
1. allesthesia
2. asomatognosia
3. anosognosia
4. extinction |
|
|
Term
| is neglect a problem with processing sensory input? |
|
Definition
| no! involves an unawareness of even the existence of the left half of space |
|
|
Term
| Ramachandran et al neglect task |
|
Definition
| tested neglect patients by holding up a mirror on their right & an object (in easy reaching distance of right hand) on left hemifield of patient so patient could see it by looking in the mirror --> asked the patient to reach for the object |
|
|
Term
| could patients who were blind to the left half of space (unilateral damage to V1 causing homonymous hemianopia) do the Ramachandran neglect task? |
|
Definition
|
|
Term
| difference in neglect patients vs. homonymous hemianopia patients asked to scan a scene (ex. "Where's Waldo?") |
|
Definition
neglect --> patient will only look at right half of the display (as measured by tracking their gaze)
homonymous hemianopia --> patients looked across both sides |
|
|
Term
| how do neglect patients perform on the Posner task? |
|
Definition
almost like cue in left ("bad") hemi-field does not affect performance because valid right is only slightly faster than invalid right
invalid left (cue in good right hemi-field, target in bad left hemi-field) we see a HUGE increase in RT |
|
|
Term
| Posner's theory for why neglect patients are particularly slow to response to a contralateral target preceded by an ipsilateral cue |
|
Definition
| patients are having problems disengaging from right "good side" cue (even when it was invalid) to left "bad side" target |
|
|
Term
| Kinebourne's "opponent processor" model of neglect |
|
Definition
| cross-inhibition between right & left hemisphere pools of attention |
|
|
Term
| Cohen et al model to show that it was possible to account for Posner's neglect results without positing a special "disengage" mechanism |
|
Definition
cue appearing in right --> activates right perception unit --> activates right attention pool --> inhibits left attention pool
recurrent activity keeps these attention units in this state until target appears |
|
|
Term
| how Cohen et al model represents neglect for Posner's neglect patients |
|
Definition
| takes out a few "neurons" in the left attention pool --> already the left attention pool has reduced activity possible because "lesion" prevents large amounts of recurrent activity --> allows for profound inhibition of the left by excitation of the right attention pool |
|
|
Term
| Cohen et al model results vs. Posner neglect patient results |
|
Definition
|
|
Term
| study done to show that patients with left hemispatial neglect are not altogether neglectful of content of left half of an image |
|
Definition
authors presented the patient with two pictures, both of houses, one with smoke coming out on the left & patient was asked what they were looking at
patients would say they were both houses & could not describe differences between the two, but when asked which house they would want to live in, they nearly always chose the house without smoke coming out of the window |
|
|
Term
| conclusion from the "smoking house" neglect study |
|
Definition
| the patients are not conscious of what is in the picture on the left side, but some sort of processing is going on because patients get a "bad feeling" about the house with the smoke |
|
|
Term
task: patients with left hemispatial neglect arising from right parietal damage were required to report, in response to each visual display, whether it contained an item on the right, an item on the left, or items on both sides & to name each present item (ring, flower, or spider)
results when emotional stimulus (spider) was shown in bilateral displays on the left |
|
Definition
| robustly escaped extinction |
|
|
Term
| conclusion from bilateral display of ring/flower/spider with patients with neglect |
|
Definition
| potent image content, although neglected, may be processed to a stage at which it acquires salience sufficient to counteract extinction |
|
|
Term
| two spatial reference frames with respect to which neglect may be defined |
|
Definition
| egocentric or allocentric |
|
|
Term
| a patient with neglect copying a picture of two flowers next to each other will draw ______ |
|
Definition
| the right half of each flower |
|
|
Term
Arguin & Bub measured the RT for a patient with left-sided neglect to name a letter presented in an array in which the other 3 elements were just filled circles
results? |
|
Definition
| patients had faster RTs for relative positioning of the letter in the array regardless of literal position in space |
|
|
Term
| Alex Pouget's explanation for Arguin & Bub's array-centered demonstration of neglect |
|
Definition
| the firing rate of the neuron for the letter doesn't change whether it is leftmost or rightmost BUT it will be the highest relative to the firing rate of the other neurons being excited because the farther left something is, the lower its firing rate will be |
|
|
Term
| do neurons with object-centered spatial selectivity exist in the cerebral cortex of the monkey? |
|
Definition
|
|
Term
| how do neglect patients perform on an experiment where a pair of stimuli are either identical or differ with respect with what is on the right or the left |
|
Definition
| patients with let brain damage are really bad at identifying pairs that differ with respect to what is on the left; patients with right brain damage are really bad at identifying pairs that differ with respect to what is on the right |
|
|
Term
| what is important about the experiment with neglect patients in which the stimuli were presented one at a time in succession by passing behind a narrow slit? |
|
Definition
| neglect effects not only processing of the left or right half of the display but rather the processing of information of the right or left half of the mental image formed from the display |
|
|
Term
| Bigiach & Luzzatti neglect experiment |
|
Definition
| neglect patients in Milan had to tell authors about aspects of the Piazza; sometimes from POV standing at palace facing the Duomo or vice versa --> patient could report landmarks from his POV "current" right compared to "current" left |
|
|
Term
| big conclusion from Bigiach & Luzzatti neglect experiment |
|
Definition
| neglect can affect even mental representations of scenes |
|
|
Term
| ventral stream - to temporal cortex --> for ______ |
|
Definition
| object vision (pattern recognition) |
|
|
Term
|
Definition
|
|
Term
| who first came up with the "stream" idea of visual processing? |
|
Definition
|
|
Term
| dorsal stream of visual processing is also referred to as controlling _____ functions |
|
Definition
|
|
Term
| parietal cortex controls both ______ & _____ visual functions (but it may be regionalized within the parietal cortex) |
|
Definition
|
|
Term
| 3 places with which parietal cortex has bidirectional connections |
|
Definition
1. visual system
2. somatosensory system
3. premotor/prefrontal cortex |
|
|
Term
| ______ is ideally suited to mediate spatial processes that are related to converging sensory signals from multiple modalities into motor outputs |
|
Definition
|
|
Term
| is parietal cortex involved in homogenous or heterogenous functions? |
|
Definition
|
|
Term
| big overall pattern of parietal cortex function |
|
Definition
| there is a general distinction between functions of medial intraparietal sulcus (superior lobule) (related to representation of the body/control of the body; use of "how" functions) vs. lateral intraparietal sulcus (inferior lobule) (related to vision & spatial cognition) |
|
|
Term
| injury to superior lobule --> ? |
|
Definition
| tactile agnosia, disorders of body image, optic ataxia |
|
|
Term
| injury to inferior lobule --> ? |
|
Definition
| contralateral neglect, impairment of attention, constructional apraxia, disorders of drawing |
|
|
Term
|
Definition
| disorder of reaching for things under visual control, trouble reaching for things on the left (even though seen perfectly), reaching under visual guidance (no trouble with reaching in general!) |
|
|
Term
| Milner experiment of optic ataxia |
|
Definition
| asking a patient to put their hand through a slot in a large board in front of them |
|
|
Term
| what is meant by "inaccurate preshaping" of hand to object in optic ataxia? |
|
Definition
"good" hand --> hand forms a pre-grasping shape with the digits to grasp a ball
you do not see this preshaping in the "bad" hand |
|
|
Term
| constructional apraxia is a common result of ______ injury |
|
Definition
|
|
Term
| constructional apraxia experiment: patients are given matchsticks & asked to make a star shape with them |
|
Definition
| results: they cannot make accurate star shapes! |
|
|
Term
| constructional apraxia experiment: patient is asked to recreate a shape with painted tiles |
|
Definition
| results: the tiles will end up just almost randomly scattered about with no image being made when you put them together |
|
|
Term
| constructional apraxia experiment: asking patients to copy shapes |
|
Definition
| more complicated shapes ("3D" cubes, those involving multiple shapes) gave more issues compared to simple shapes (just drawing a circle or triangle) |
|
|
Term
| results of constructional apraxia patient asked to freely draw something like a "bicycle" or "face" |
|
Definition
| you may be able to pull out individual parts in the drawing (e.g. the wheels, handlebars, nose, mouth, etc.) BUT their relations to each other will not be correct so overall it looks like a scribble |
|
|
Term
| can constructional apraxia patients recognize things when they see them? |
|
Definition
| yes but cannot imagine them to draw them |
|
|
Term
| why the mingling of motor guidance (how) with spatial cognitive (where) functions? |
|
Definition
| over the course of evolution, mechanisms for representing where things are relative to the body (in the service of motor guidance) may have ramified into mechanisms for representing where things are relative to each other (in the service of spatial cognition) |
|
|
Term
| Brodmann areas: is human parietal cortex the same or different from monkey cortex? |
|
Definition
|
|
Term
| as we go from medial --> lateral in monkey intraparietal sulcus, we see functions changing from _____ --> ______ |
|
Definition
| sensing/controlling body --> visual systems |
|
|
Term
| area LIP was first discovered in ______ |
|
Definition
| anesthetized monkeys by recording in response to flashed stimulus |
|
|
Term
| memory guided saccade task |
|
Definition
monkey has to wait, after seeing a stimulus, before making an eye movement to its location
neurons in area LIP fire in response to the stimulus, during the delay period, & at the time of the movement |
|
|
Term
| results of MGS task & recordings from area LIP |
|
Definition
| LIP has sensory responses, carries motor information, & activity related to attention/planning eye movements/holding a location in working memory |
|
|
Term
| Andersen et al study of the angle-of-gaze effects in LIP taught us ______ |
|
Definition
| neurons in area LIP have visual receptive fields that are fixed with respect to retina |
|
|
Term
| Zipser & Andersen model for the gaze gradient in LIP neurons: inputs |
|
Definition
| where in the visual field the retinal input layer was for the stimulus & the gaze of angle of the monkey |
|
|
Term
| Zipser & Andersen model for the gaze gradient in LIP neurons: output |
|
Definition
| signal representing where the image was relative to the head |
|
|
Term
| Zipser & Andersen model for the gaze gradient in LIP neurons: conclusion |
|
Definition
| LIP neurons may represent a processing state between V1 early stage (neurons signaling where the retinal image is) & a later stage in which neurons represent where things are relative to the head |
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Term
| neurons in VIP have transitional properties that relate to ______ |
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Definition
| transition from areas related to vision/attention to functions related to sensing/controlling the body |
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Term
| 2 things VIP neurons respond to |
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Definition
1. somatosensory stimuli
2. visual stimuli |
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Term
| Duhamel et al study for VIP neural receptive fields |
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Definition
| some neurons in area VIP respond to both cutaneous & visual stimulation & have matching bimodal receptive fields defined with respect to the body |
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Term
| what does it mean that in VIP neurons "congruence is maintained as gaze shifts"? |
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Definition
| visual receptive field shifts on the retina to maintain receptive fields with the cutaneous receptive field |
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Term
| Snyder et al addition to the MGS task |
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Definition
| interloped with trials in which the monkey had to make memory-guided saccades were trials in which the monkey had to make memory-guided reaches |
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Term
| Snyder et al MGS task + reaches results |
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Definition
| neurons in MIP responded to cues but only maintained sustained delay-period activity only on trials in which the monkey was instructed to execute a reach |
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Term
| goal of Andersen study where he had monkey have both a starting fixation point for eyes & a separate starting point for holding hand in reach to target task |
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Definition
| ask what factors neurons were sensitive to regarding their differential firing for different reaches |
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Term
| conclusion from Andersen reach to target task |
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Definition
| what differentiates conditions to where firing was strong was the reach direction as defined by where the monkey was looking! |
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Term
| How did Sakata et al discover that neurons in area AIP fire during grasping of specific objects or in conjunction with seeing them or both? |
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Definition
| recording from AIP while monkey manipulated different objects that required different kinds of grasps |
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Term
| AIP appears to be the area that connects ______ input & _____ output for objects we will grasp |
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Definition
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