Higher Cortical Function While Awake

Question 1

What is Capgrass syndrome? What is it indicative of?

Answer 1

Belief that someone is an impostor of the real person. Indicative of prefrontal cortex damage

Question 2

What are the two broad categories of higher cortical function?

Answer 2

1. Nonexecutive - tools in the toolbox, including sensory + motor capacities, memory, emotions, and attention
2. Executive - Neural functions CONTROLLING nonexecutive function, i.e. decisionmaking, judgment, self control

Question 3

What are unconscious functions?

Answer 3

Brain activities which do not enter awareness, comprises the majority of functions. We are often only aware of the very end result of sensory processing, even in movement (praxis) we are only aware of the sensory correlates of movement

Question 4

What are conscious functions used for? Are we conscious when asleep?

Answer 4

Learning and memory, and also how they express themselves. It is the awareness, which is the integrative hub of nervous system activity to accomplish our goals.

Dreaming is considered conscious

Question 5

What is the anatomy of feedforward information pathway in the cortex? Where are memories stored?

Answer 5

123,321 from sensory to motor.

Memories are stored in input / output tracks interacting with executive control, which is always the 3rd level of motor / sensory. Secondary is processing.

Question 6

What are the reciprocal connections of the cortex called?

Answer 6

Forward connection = feedforward

Backward connection = feedback

Question 7

What layer do thalamocortical loops interact with reciprocally?

Answer 7

Layer 6, both feedforward and feedback, unless it’s a primary relay pathway.

Question 8

Where does primary sensory cortex receive information and what is the modality?

Answer 8

Receives info from thalamus to layer 4, from thalamic relay nuclei. It is unimodal - dedicated to only one sensory modality. It is for introduction of sensory input to the cortex.

Question 9

What projects to the secondary sensory cortex and what is the function?

Answer 9

Receives unimodal information from primary sensory cortex, functions to add complexity to primary info and serve as the primary input for sensory memory areas.

Question 10

What are the two main tertiary sensory cortices and what is their modality?

Answer 10

1. PTO (parietal-temporal-occipital) cortex
2. Limbic association cortex

These are multimodal, and integrate information from multiple secondary cortices.

Question 11

What is the PTO cortex’s function?

Answer 11

Fuses all senses together to generate our sensation. Serves as main input to both sensory memory system and tertiary motor cortex. Also gives input to the limbic association cortex

Question 12

What is the limbic association cortex and its function? What is its modality?

Answer 12

Rhinal cortex (area 28)

It serves to give direct input to the sensory memory system, and also receives input from teritary motor cortex.

It is “supramodal” because it fuses the sensory input with thoughts of executive function (goals, motivations, attention).

Question 13

What is the tertiary motor cortex also called, and its modality?

Answer 13

Also called prefrontal association cortex, it is supramodal, as it starts our cortical output based on goals, desires, and motivations

Question 14

What are the two main regions of the prefrontal association cortex and what do they do? How do you remember?

Answer 14

1. Dorsolateral prefrontal cortex (10, 46) - Seat of reasoning, logical and sequential thinking, planning, site of short-term memory. D is for doug stamper
2. Orbitofrontal prefrontal cortex (11)- Seat of wisdom, emotional expression and reactions, conscience, judgment. O is for Oprah

Question 15

What is the function of the secondary motor cortex?

Answer 15

Stores movement commands, plugs into primary motor cortex, secondary somatosensory cortex (tactile movement), and BG + cerebellum

Question 16

What is the function of the primary motor cortex?

Answer 16

Plug into motor neurons of the spinal cord, and cause contraction of muscles

Question 17

What number is Broca’s area? What type of cortex is it considered?

Answer 17

Area 45, considered secondary cortex because it just controls speech muscles

Question 18

What area is Wernicke’s area? What type of cortex is it considered?

Answer 18

Area 22, considered tertiary cortex because it processes visual, auditory, and somatic secondary cortex

Question 19

What area of the cortex is most important for declarative memory usage?

Answer 19

Entorhinal area (limbic association cortex) - area 28,35,36

This is supramodal tertiary cortex

Question 20

What type of cortex are areas 18 and 19?

Answer 20

Secondary sensory

Question 21

What type of cortex is area 8?

Answer 21

FEF -> motor secondary

Question 22

How are declarative memories formed and stored?

Answer 22

Formed from inputs from secondary and tertiary sensory cortices which are part of the “rhinal cortices” in the temporal lobe. These plug into the hippocampus which “burns the DVD” and stores the memories back in the rhinal cortices.

Question 23

What serves a modulatory input in memory formation?

Answer 23

prefrontal cortex, amygdala, and reticular activating system which allow our memories to be molded by our goals and motivations

Question 24

How are procedural memories stored? Why is this relevant?

Answer 24

Via execution of motor activities, a complex set of pathways links association cortexes, as well as cerebellum, BG, and secondary + primary motor cortices to form memory of muscle actions

Relevant because damage to any one of these will only lead to a minor decrease in ability to learn procedural memories.