341 Exam 4 - Cerebral Cortex

25 billion

How many neurons does the cerebral cortex contain?

100 trillion

How many synapses does the cerebral cortex contain?

true

True or false: while only a few millimeters thick, the cerebral cortex accounts for nearly half the weight of the brain

motor, sensory, learning, memory, language, affective

The cerebral cortex mediates 

• Voluntary ____ control 

• ____ perception

• ____

• ____

• ____ 

• ____ processes 

neocortex

newest and most superficial area of the brain, containing six layers arranged parallel to the cortical surface

6

The neocortex contains how many layers arranged parallel to the cortical surface?

localized

Certain areas of cortex are specialized to processes certain types of information, and therefore functions are ____ to specific cortical areas.

plastic

Despite localization of function, brains are ____ and can take on new and different functions given the right conditions. 

Korbinian Brodmann

German neurologist who first recognized in the early 1900s that different cortical areas are subtly different in structure and function and can therefore be mapped

Brodmann’s areas

regions of cortex assigned numbers based on their structure and function

primary sensory cortex, primary motor cortex, association cortex, limbic cortex

What are the four general areas that the cortex can be divided into?

primary sensory cortex

one of four general areas that the cortex can be divided into; detects sensory stimuli and receives input from the thalamus

primary motor cortex

one of four general areas that the cortex can be divided into; initiates voluntary action and gives rise to much of the corticospinal and corticobulbar tracts

association cortex

one of four general areas that the cortex can be divided into; carries out higher-order information processing

limbic cortex

one of four general areas that the cortex can be divided into; described as the “emotional brain”

association cortex

Which of the four general areas of cortex occupies the most cortical space? 

primary somatosensory cortex (S1, Brodmann’s areas 3, 2, 1)

primary sensory cortex located on the postcentral gyrus in the parietal lobe; impairment to this cortical area leads to impaired ability to discriminate intensity or localize sensations on the contralateral side of the body; impairment typically does not make sensation absent

false

True or false: impairment of the primary somatosensory cortex (S1, Brodmann’s areas 3, 2, 1) typically makes somatosensory sensation absent.

true

True or false: impairment of the primary somatosensory cortex (S1, Brodmann’s areas 3, 2, 1) typically does not make somatosensory sensation absent.

3, 2, 1

The primary somatosensory cortex is assigned which Brodmann’s area number(s)? 

primary somatosensory cortex

Which primary sensory cortex is referred to as “S1”?

primary visual cortex

Which primary sensory cortex is referred to as “V1”?

primary visual cortex

Which primary sensory cortex is referred to as “striate”?

17

The primary visual cortex is assigned which Brodmann’s area number(s)? 

primary visual cortex (V1, striate, Brodmann’s area 17) 

primary sensory cortex located on the occipital lobe; impairment to this cortical area leads to cortical blindness in the contralateral visual field 

primary auditory cortex (A1, Brodmann’s area 41) 

primary sensory cortex located on the transverse temporal gyri of the temporal lobe; impairment to this cortical area leads to impaired ability to localize sound and minor hearing loss on contralateral side 

41

The primary auditory cortex is assigned which Brodmann’s area number(s)? 

primary auditory cortex

Which primary sensory cortex is referred to as “A1”?

primary olfactory cortex, primary gustatory cortex, primary vestibular cortex

Besides the primary somatosensory cortex (S1, Brodmann’s areas 3, 2, 1), primary visual cortex (V1, striate, Brodmann’s area 17), and primary auditory cortex (A1, Brodmann’s area 41), name three additional primary sensory cortices.

M1

What is another name for the primary motor cortex?

4

The primary motor cortex is assigned which Brodmann’s area number(s)? 

primary motor cortex (M1, Brodmann’s area 4)

cortex located on the precentral gyrus of the frontal lobe; impairment to this cortical area leads to contralateral paresis

topographical organization

Primary sensory and motor cortices area characterized by a ____ ____ in which the body surface, range of audible frequencies, or representation of the outside world, is mapped onto the cortical surface.

unimodal association cortex, multimodal association cortex

Name the 2 types of association cortex.

heteromodal association cortex

What is another term for “multimodal association cortex”? 

unimodal association cortex

higher-oder processing mostly for a single sensory or motor modality; usually adjacent to a primary motor or sensory cortex

agnosia

sensory without perception; often caused by impairment to sensory unimodal association cortices

multimodal association cortex

association cortex involved in integrating functions from multiple sensory and/or motor modalities

somatosensory association cortex

sensory unimodal association cortex involved in interpretation of somatosensation; impairment to this cortical area leads to astereognosis

visual association cortex

sensory unimodal association cortex involved in interpretation of visual information; impairment to this cortical area leads to visual agnosia

auditory association cortex

sensory unimodal association cortex involved in interpretation of auditory information; impairment to this cortical area leads to auditory agnosia; also contains Wernicke’s area

Wernicke’s area

specific area of the auditory association cortex located in the posterior part of the superior temporal gyrus and involved in language interpretation

premotor cortex and supplementary motor area

unimodal association cortex involved in motor planning and postural adjustments; impairment to this cortical area leads to limb apraxia, motor preservation, etc.

Broca’s area

area of cortex location in the opercular and triangular parts of the inferior frontal gyrus and involved in language expression

posterior multimodal association cortex, anterior multimodal association cortex

Name the 2 multimodal association cortices.

posterior multimodal association cortex

multimodal association cortex located where the parietal, occipital, and temporal lobes meet; integrates sensory information and sends to anterior multimodal association cortex

right

Which hemisphere is dominant for spatial attention? (right or left)

left-side

Which type of neglect is more common: right-side or left-side? 

right

Contralateral neglect usually occurs after damage to which posterior multimodal association cortex? (right or left)

left

Which hemisphere is more involved in compiling sensory information needed to accurately plan movements? (right or left) 

apraxia

inability to perform some actions, even though required muscles are intact; may be able to perform the action in a different context; may be associated with damage to the left posterior multimodal association cortex

left

Apraxia usually occurs after damage to which posterior multimodal association cortex? (right or left)

anterior multimodal association cortex

What is another term for the prefrontal cortex? 

anterior multimodal association cortex

multimodal association cortex located in the frontal lobe that is responsible for executive functions, including planning, insight, foresight, and basic aspects of personality

dorsolateral prefrontal cortex, ventromedial prefrontal cortex

What are the two areas of the anterior multimodal association cortex?

dorsolateral prefrontal cortex

part of the anterior multimodal association cortex that integrates sensory data from the posterior multimodal association cortex and uses it for executive functions; also plays critical role in working memory

ventromedial prefrontal cortex

part of the anterior multimodal association cortex that integrates emotions from the limbic structures and uses it for executive functions

ventromedial prefrontal cortex

Which part of the anterior multimodal association cortex was damaged in Phineus Gage after his accident?

dorsolateral prefrontal cortex

Which part of the anterior multimodal association cortex is involved in working memory?

disinhibition

inability to constrain emotions or behaviors; may result from damage to the anterior multimodal association cortex

false

True or false: damage to the anterior multimodal association cortex severely affects intelligence. 

sensory, unimodal, posterior, anterior, premotor, motor

The following describes the flow of information through the prefrontal cortex

• primary ____ cortex

• ____ association cortex

• ____ multimodal association cortex

• ____ multimodal association cortex

• ____ cortex to access a motor plan

• primary ____ cortex to implement motor plan

lateralization

There is evidence of ____ of brain function, in which certain mental processes are mainly specialized in one hemisphere

corpus callosum, anterior commissure

Name the 2 major connections between the right and left cerebral hemispheres.

left

To which cerebral hemisphere are language functions lateralized? 

right

To which cerebral hemisphere are attention functions lateralized? 

aphasia

inability to use language; usually associated with damage to the left hemisphere

left

Is aphasia usually associated with right or left hemisphere damage? 

nonfluent aphasia, fluent aphasia

Name the 2 broad categories of aphasia, based on the ease with which words can be produced.

nonfluent

Is Broca’s aphasia typically nonfluent or fluent?

fluent

Is Wernicke’s aphasia typically nonfluent or fluent?

Broca’s aphasia

typically nonfluent aphasia in which individual produces few words and with great difficulty, but language comprehension is usually intact

yes

Is language comprehension typically intact in Broca’s aphasia?

no

Is language comprehension typically intact in Wernicke’s aphasia?

Wernicke’s aphasia

typically fluent aphasia in which sentences are defective and individual has difficulty comprehending language

paraphasia

substitution of one letter or word for another; may be seen in Wernicke’s aphasia

neologism

insertion of new and meaningless word; may be seen in Wernicke’s aphasia

jargon aphasia

stringing together of words and phrases in an order that conveys little or no meaning; may be seen in Wernicke’s aphasia

paraphasia, neologisms, jargon aphasia

Name 3 symptoms that may be seen in Wernicke’s aphasia. 

global aphasia

aphasia that involves both Broca’s and Wernicke’s areas

prosody

the rhythmic and musical aspects of speech; typically a right hemisphere function

right

Is prosody typically a right or left hemisphere function?

consciousness

a state of self-awareness in which it is possible to direct attention and manipulate abstract ideas; arises from interactions among neural structures

coma, vegetative state, minimally conscious state

Name 3 terms used to differentiate subtle differences in arousal, awareness, responsiveness, and duration of unconsciousness.

coma

state of unconsciousness in which there is no arousal, awareness, or responsiveness

vegetative state

state of unconsciousness in which there is arousal, but no awareness or responsiveness

minimally conscious state

state of unconsciousness in which there is arousal and emerging awareness and responsiveness  

sleep

a normally occurring state of unconsciousness from which we can be aroused; an active process that may involve the hippocampus actively consolidating the day’s memory for storage