Lecture 3 - Cerebral Cortex Organization and Function

Question 1

Granular (Stellate) Neurons

Answer 1

Short axons, interneurons, both excitatory (glutamate) and inhibitory (GABA)

Question 2

Fusiform Neurons

Answer 2

Smaller output neurons

Question 3

Pyramidal Neurons

Answer 3

Large output neurons

Question 4

Layer IV of Cerebral Cortex

Answer 4

Termination of most incoming specific sensory signals

Question 5

Layer V and VI of Cerebral Cortex

Answer 5

Origin of most output signals; fibers to thalamus from VI

Question 6

Layers I, II, and III of Cerebral Cortex

Answer 6

Intracortical association functions

Question 7

Primary Motor Areas

Answer 7

Direct connections with specific muscles

Question 8

Primary Sensory Areas

Answer 8

Detect specific sensations

Question 9

Secondary Motor Areas

Answer 9

Provide patterns of motor activity

Question 10

Secondary Sensory Areas

Answer 10

Analyze meanings of specific sensory signals

Question 11

Parieto-Occipitotemporal Association Area

Answer 11

Has area for analysis of spatial coordinates, Wernicke’s area, angular gyrus area, and area for naming objects

Question 12

Prefrontal Association Area

Answer 12

Receives preanalyzed sensory information (esp. concerning spatial coordinates) necessary for planning effective movements; output passes through caudate portion of basal ganglia; carries out “thought” processes in the mind

Question 13

Limbic Association Area

Answer 13

Concerned with behavior, emotions, and motivation

Question 14

Broca’s Area

Answer 14

Provides circuitry for word formation; works closely with Wernicke’s area; almost always dominant on left side of brain

Question 15

Wernicke’s Area

Answer 15

Language comprehension; area where somatic, visual, and auditory association areas all meet one another in the posterior part of the superior temporal lobe; located on left side in almost all people

Plays greatest single role of any part of the cerebral cortex for intelligence

Question 16

Prefrontal Lobotomy Characteristics

Answer 16

Loss of ability to solve complex problems, inability to string together sequential tasks to reach complex goals, inability to do several parallel tasks at the same time, decrease in level of aggressiveness (ambition), inappropriate social responses, inability to carry through long trains of thought, loss of purpose while performing usual motor pattern functions

Question 17

Abilities due to Brain’s Working Memory

Answer 17

Prognostication, planning for future, delay in response to incoming sensory signals, ability to consider consequences of motor actions, ability to solve complicated mathematical, legal, or philosophical problems, control of activities in accord with moral law

Question 18

Corpus Callosum

Answer 18

Major commissure between the two hemispheres

Question 19

What happens when you cut the corpus callosum?

Answer 19

Blocking of transfer of information from Wernicke’s area to nondominant motor cortex; prevention of the transfer of somatic and visual information from right hemisphere into wernicke’s area, results in 2 entirely separate conscious portions of the brain

Question 20

Declarative Memory

Answer 20

Memory of various details of an integrated thought; might include memory of surroundings, time relationships, causes of experience, meaning of experience, or deductions as a result of experience

Question 21

Reflexive (Skill) Memory

Answer 21

Associated with motor activities

Question 22

Short-Term Memory

Answer 22

Exemplified by memory of a telephone number; lasts only as long as person thinks of number or facts (seconds)

Question 23

Intermediate Long-Term Memory

Answer 23

Lasts many minutes or weeks; may become long-term memory (more permanent) if memory traces are activated enough

Question 24

Mechanism for Facilitation

Answer 24

Stimulation of facilitator presynaptic terminal at the same time that sensory terminal is stimulated causes serotonin release at facilitator synapse; serotonin receptors in sensory terminal membrane activate adenyl cyclase to cAMP, which activates part of K+ channel; K+ channel is blocked for minutes to weeks

Question 25

What does lack of K+ conductance cause?

Answer 25

Greatly prolonged action potential in synapse terminal

Question 26

What does prolonged action potentials cause?

Answer 26

Prolonged activation of Ca2+ channels

Question 27

What does prolonged activation of Ca2+ channels cause?

Answer 27

Prolongs transmitter release

Question 28

Structural Changes in Long-Term Memory

Answer 28

Increase in vesicle release sites for secretion of transmitter substance, increase in number of transmitter vesicles released, increase in number of presynaptic terminals, and changes in structures of the dendritic spines