Prefrontal Cortex/Memory & Intellect/TBI/Sleep

AC Copy

lateral, medial, ventral

parts of the prefrontal cortex

executive functions (higher-level thinking)

• deciding on a goal

• planning, carrying out a plan, changing the plan

divergent thinking

• ability to think of a variety of possibilities

functions of the lateral prefrontal cortex

you say the color, not the word, as fast as you can

• measures selective attention

What is the Stroop test?

can impair one’s ability to set goals, formulate a plan, and think flexibly. (Ex. following a GPS into a pond - over exaggerated example)

How can a lesion to the lateral prefrontal association cortex affect someone?

emotions, self-awareness, and motivation

functions of the medial prefrontal association cortex

apathy (not caring/lacking concern), lack of emotions and/or insight, paranoia, delusions

How can a lesion to the medial prefrontal association cortex (limbic association area) affect someone?

interoceptive cortex (insula)

cortex that mediate internal awareness

interoception

ability to identify what is going on in our own bodies

Ventral Prefrontal Cortex

cortex that connects with areas regulating mood and affect (social behavior)

• impaired in feeling empathy, embarrassment, guilt and regret

• intact intellectual ability but uses poor judgement

• impulsive, does not conform to social norms

• shows no elevation of galvanic skin response when choosing a tisk card in a card game

What do lesions in the ventral prefrontal cortex cause?

working memory

memory: goal relevant information for a short time (ex. Cannot remember if you tell them you are seeing them tomorrow or what we will work on tomorrow)

declarative memory

memory: facts, concepts, locations

procedural memory

memory: skilled movements and habits, doing things (ex. How to work a cellphone, the coffee maker)

amnesia

loss of declarative memory

intellect

the ability to form concepts to reason

closed brain injury

brain injury resulting from falls, motor vehicle crashes, etc.

• focal damage and diffuse damage to axons in the brain

• broad effects

• no penetration to the skull

open brain injury

brain injury resulting from bullet wounds, etc.

• largely focal damage, penetration of skull

immediately: tissue damage, bleeding, swelling

• diffuse axonal injury

What happens after a brain injury?

decreased goal-directed behaviors, executive functions, judgement, attentional problems, poor divergent thinking

dysfunction in the dorsolateral prefrontal cortex

impulsiveness and inappropriate behaviors

dysfunction in the ventral prefrontal cortex

autonomic dysregulation

results from compression of brainstem or thalamus

• heartbeat, breathing, and eye movements slow

• muscles relax, twitch

• brain waves being to slow down

stage 1 of sleep (light) (1-7 min))

• heartbeat and breathing slow more

• muscles relax more

• body temp drops, eye movements stop

• brain wave activity slows

stage 2 of sleep (light (10-25 min))

• heartbeat and breathing slow to their lowest levels

• muscles stay relaxed

• brain waves slow more

stage 3 of sleep (deep (20-40 min))

• eye moves rapidly side to side

• breathing speeds up and be become irregular

• heart rate and bp increase

stage 4 of sleep (REM (20-40 in))

vigilance

the action or state of keeping careful watch for possible danger or difficulties