Cognitive Neuroscience Exam 2

superior

Layers of cells at the back of the eye that register light and send that information to the brain

Retina

What tissue is retinal tissue is derived from?

Neural tissue during embryonic development

Where does parallel processing start?

The photoreceptors in the cell

Rods and cones contain pigments that absorb ____ energy and transform it into _________ energy used in the nervous system

Light; electrochemical

Rods contain one pigment, _________, which is sensitive to very small amounts of light

Rhodopsin

There are three types of cones.  Each contains a different pigment sensitive to a different wavelength in the visible light spectrum. What are the colors?

Blue, green, and red

Cones are packed more densely in the ________

Fovea

rods are located more in the __________

Periphery

Many rods feed into a ________ _____, compared to only a few cones

Ganglion cell

Their axons extend toward the brain and form the optic nerve

Ganglion cells

Tonotopic mapping refers to organization of the auditory cortex according to

sound frequency

What structure in the ear translates sound vibrations into neural signals

cochlea

In center-surround receptive fields the light in the center do what, and in the surrounding do what?

light in the center will excite, light in the surrounding will inhibit

What does MEG do more accurately than EEG?

provides information about how deep within the brain the source is located

Describe how ganglion cells function

Their axons extend toward the brain and form the optic nerve

What are the two types of ganglion cells?

magnocellular cells and parvocellular cells

This type of ganglion cells are large and respond to coarse pattern and detect rapid motion

magnocellular

This type of ganglion cells are small, preserve color information and slower

parvocellular

What is the main perceptual effect of cerebral achromatopsia?

only perceiving shades of grey and not colors

A patient can identify objects but cannot reach for them. This indicates damage in the _____ pathway

dorsal (where)

The __________ pathway involved input from M ganglion cells. It sends visual information from the retina to the superior colliculus.

tectopulvinar

Uses a small, specific group of neurons to represent a specific item

sparse coding

pattern of activity across a large population of cells codes for individual objects

population coding

A person cannot recognize familiar faces but can identify objects normally.

Prosopagnosia

Damage to the ventral pathway causes _____ agnosia

visual

What is the sequence that represents the flow of auditory information?

Cochlea → Brainstem → Midbrain → Thalamus → Cortex

There is a particular cell in the ventral processing stream whose job is to fire when you see a particular object. It is an extreme of sparse coding.

Grandmother cell theory

What are the mechanisms that allow us to determine the direction of sound?

Interaural time difference and Interaural intensity difference

Somatosensory agnosia, also known as tacticle agnosia, refers to?

the inability to recognize objects through touch

EEG and ERP are great at _____ and poor at _______

temporal resolution; spatial resolution

The striate cortex, also known as the primary visual cortex, has what kinds of cells?

Simple, complex, and hyper-complex

What ability is an individual with associative agnosia likely to retain?

the ability to copy pictures

6 layers folded in a knee shape, what structure is this?

Lateral Geniculate Nucleus

What are the three layers in the LGN?

magnocellular, parvocellular, and koniocellular

Which layers receive from inputs from ganglion cells and the superior nucleus

Koniocellular

What does electroencephalography (EEG) primarily record?

summed postsynaptic electrical activity of neurons

Retinotopic mapping in the LGN ensures what?

each layer has a map of its own so information doesn’t get jumbled up

What is used to map out retinotopic mapping in the LGN?

single-cell recording and fMRI

Most feedback connections to the LGN comes from the _______ ________ ________

primary visual cortex

Projections from the LGN to the primary visual cortex maintain their ______ __________

spatial organization

In the primary visual cortex, mm of cortical surface are devoted to one degree of the world

cortical magnification factor

Based on evidence from monkeys, damage to the magnocellular layer of the LGN would most likely result in difficulty with?

determining the motion of a stimulus

In orientation specificity, many cells in ___ and ______ _______ are tuned to respond to edges with a particular orientation.

V1; higher areas

What did Huber & Weisel discover about orientation specificity?

Simple cells responded to a certain orientation

Auditory information travels through the different structures of the auditory system in what order?

cochlea, superior olive, inferior colliculus, MGN, A1

Think about a single neuron in the left LGN. It receives input from

either the left eye or right eye, depending on which layer of the LGN it is in

Coincidence detectors and delay lines are part of the brain mechanism that

uses temporal differences to localize sounds in the medial superior olive

What does EEG primarily record?

summed postsynaptic electrical activity of neurons

based on evidence from monkeys, damage to the magnocellular layer of the LGN would most likely result in difficulty with?

determining the direction of motion of a stimulus

in the human visual system, neurons in the LOC (lateral occipital cortex) respond most strongly to?

object shapes

Which part of the eye consists of layers of cells that register light beginning the process of representing the visual world?

retina

In the striate cortex, cells are segregated into columns according to which eye sends them information. These columns are referred to as ________.

ocular dominance columns

The auditory canal is located in ________.

the outer ear

Which step of the auditory pathway comes after the inferior colliculus?

medial geniculate nucleus

What is the appropriate order of the ventral processing stream?

V1 to V2 to V4 to anterior inferotemporal areas.

What kind of visual processing do large receptive fields allow for?

object recognition

The word agnosia is best described as meaning ________.

without meaning

Someone with associative agnosia would have difficulties ________.

identifying what they see

Developmental prosopagnosia likely has a genetic component and is thought to be present in approximately ____ percent of the general population.

2

What is true of a patient with developmental prosopagnosia?

Individuals can sometimes have trouble recognizing family members or themselves

Neural modules within the ventral stream may be specialized for recognising specific categories of objects. There is evidence for four types of specialized modules. Which acronyms represent these four types?

VWFA, PPA, EBA, FFA

Which neural modules within the ventral stream is most specialized for recognising faces?

FFA

What are the three ways that auditory agnosia can manifest?

verbal auditory, nonverbal auditory, and mixed auditory

If a person has ________ agnosia, the ability to attach meaning to nonverbal sounds is disrupted.

nonverbal auditory

How many paths separate pathways project from the dorsal stream to other brain regions to support different spatial functions?

3

Which do humans find more challenging to distinguish?

left from right

Research has shown that cells in the ________ are responsive to depth information in both the form of binocular disparity cues and the form of motion parallax cues.

MT

Dorsal stream cells also integrate ________ as a cue for depth because it can provide information about how far away something is because viewing a pattern that is closer has more details than far away patterns.

texture

What are the two frames of reference for coding spatial information?

egocentric and allocentric

Someone who shows spatial neglect of their left side and neglect that is within their reach is said to have which kind of neglect?

peripersonal

What is another name for area MT (which, along with MST, is important for perceiving motion)?

V5

Optic ataxia is a disorder of ________.

visually guided reaching

Which task might be used to study how dorsal stream cells can differentiate between the location of a stimulus and the location of an intended action?

anti-saccade task

A patient is unable to construct new representations of environments, although they are still able to navigate successfully around previously known or previously learned environments. They most likely have which condition?

anterograde disorientation

Diffusion tensor imaging (DTI) is helping for providing information about ________.

white matter

What are the two advantages of PET?

provide information on metabolism, demonstrate the distribution of neurotransmitter binding in people

What does the BOLD signal measure?

Changes in the magnet signal between oxygenated and deoxygenated blood

Which is more invasive? Transcranial direct current stimulation (tDCS) or transcranial magnetic stimulation (TMS)?

TMS, tDCS is generally safe

Optical recording methods use information about what aspects of light to to determine where and when brain activity is happening?

Absorption and scattering

is used to examine the frequency of the summed electrical signal of synchronous firing in the dendrites of populations of neurons, and can be used to distinguish states of alertness, drowsiness, and sleepiness.

EEG

Data comes from; individuals with localized lesions/ Psychiatric or neurological syndromes/ certain

behavioral characteristics

clinical participant populations

Data comes from; neurologically intact individuals

reference population

Methods that determine brain anatomy (structural function)

CT, MRI, and DTI

Methods that localize brain activity

PET, fMRI

Methods that involve electromagnetic recording of brain activity

EEG, ERP, MEG

Allows replicable patterns to be discovered in data and generalized to

new situations

machine learning example

in the striate cortex, these cells respond best to an edge of a specific orientation

simple cells

in the striate cortex, these cells respond best to certain line orientations, but less picky about

the location of the line than simple cells.

complex cells

in the striate cortex, these cells respond best to lines of certain

orientation and certain length. A.K.A end stopped cells.

hyper complex cells

In the striate cortex, these columns have cells that prefer a given line orientation are grouped

together

orientation columns

In the striate cortex, these columns have cells segregated according to which eye sends

them input

ocular dominance columns

In the striate cortex, this column has cells that are all tuned to respond to stimulation at a particular

spatial location.

hypercolumn

No conscious experience of seeing because of extensive damage to the striate cortex, yet are able to make

rudimentary visual discriminations

blindsight

Which area in the striate cortex is sensitive to color?

V4

Becomes larger as we move further along the ventral processing stream

receptive field

At some level, our mental representation of objects is fairly

abstract

invariance in recognition

Brain’s categorization is constant regardless of the form of the

cue that represents the object.

form-cue variance

Ability to recognize objects seen from different angles,

positions, sizes, and kinds of illumination

perceptual constancy

Part of ventral stream anterior to the retinotopically mapped extrastriate areas V2 and V4, active in object recognition, more responsive to shapes than tectures

Lateral Occipital Cortex (LOC)

Important for analyzing parts of objects (Local)

left ventral stream