Brain and Behavior Midterm 3

Role of the Right Hemisphere

our ability to detect the “coloring of speech” including rhythm, timing, tone, and emphasis of speech (prosody)

Aphasia

a disorder that impairs a person’s ability to process language, but does not affect intelligence or IQ

Broca’s Area

Area in left frontal lobe responsible for motor commands associated with speech

Broca’s Aphasia

Disruption of language production and expressing oneself (even through ASL), but can understand speech

Wernicke’s Area

Area in rear left temporal lobe that contains “sound images” of words, allowing us to interpret the meanings of words

Wernicke’s Aphasia

Ability to produce language that sounds normal, but does not make sense, and lacks comprehension of speech

Conduction Aphasia

damage to arcuate fasiculus causing problems with producing appropriate responses to language, poor speech repetition, and tendency to lose train of thought while speaking

Arcuate fasciculus

links Wernicke’s and Broca’s areas as well as the frontal lobe with the temporal and parietal lobes

Role of Left Hemisphere

verbal processing

Split-brain subjects

have their corpus callosum severed, causing their two hemispheres of the brain to act independently of each other because they are no longer able to share information

Declarative memory

things that you can explain to others by telling them such as daily episodes, words and their meanings, or history

Non-declarative (procedural) memory

things that you can explain to others by showing them such as motor skills or puzzle-solving skills

Immediate memory

ongoing experiences we are not consciously thinking about that we can hold in mind for fractions of a second

Working memory (short-term memory)

ability to hold 7-10 items in mind for seconds to minutes to achieve a goal, but requires attention (Ex. hunting for objects)

Long-term memory

retaining information for days, weeks, or life (ex. skills, phone numbers of family members)

Memory consolidation

method of converting items in working memory to long-term memory, requiring rehearsal

Primacy effect

when it is easier to remember words at the beginning of a list, usually requiring practice or some kind of technique

Recency effect

when it is easier to remember words at the end of a list because they are still in short-term memory

Amnesia

partial or total loss of memory

Retrograde amnesia

difficulty with recalling previous information

Anterograde amnesia

difficulty with learning new information or making new memories

Patient H.M case study

had profound anterograde amnesia, causing him to be unable to consolidate new long-term memories, but memories from pre-surgery life and ability for procedural learning remained

Semantic memory

generalized declarative memory

Episodic memory

detailed autobiographical memory (day-to-day happenings)

Hippocampal Place Cells

population of cells in the hippocampus that fire based on where you are in space, contributing to our ability to form spatial memories

Mass action principle

degradation of learning and memory is solely dependent on the amount of cortex damaged

Role of synapses in learning and memory

synapses can be strengthened and structurally changed to receive more inputs when experience causes a permanent change in behavior (learning)

Long term potentiation (LTP)

increase in synaptic strength

Long term depression (LTD)

decrease in synaptic strength

Language is lateralized

because the left hemisphere dominates the management of language production and comprehension

Language is localized

because language functions are specifically organized into Wernicke’s and Broca’s areas

Where does consolidation occur?

Hippocampus

Dementia

a progressive decline in mental/executive functioning, memory, and intellectual skills plus one or more additional impairments

Aphasia

additional impairment that can come with dementia characterized by problems with language

Apraxia

additional impairment that can come with dementia characterized by problems with complex movements

Agnosia

additional impairment that can come with dementia characterized by problems with identifying objects

Alzheimer’s symptoms

these include confusion with time or location, misplacing items, unfounded emotions, withdrawing from social activities, difficulty solving problems, etc.

MRI scan

demonstrates loss of brain tissue and structural changes of the brain

PET scan

demonstrates overall brain activity and functional changes of the brain

Senile plaques

found in extracellular space and are made up of B-amyloid protein

Senile plaques pathology

when senile plaques lose their functions and clump together, forming molecular fragments

Neurofibrillary tangles

bundles of filaments made of tau protein arranged in a helix, found in intracellular space

Tangles pathology

Alzheimer’s patients have elevated levels of tau, causing the filaments to tangle up and no longer be straight

Nucleus basalis pathology

loss of acetylcholine-containing neurons, resulting in a loss of neuronal connectivity

Neuropathology symptoms

characterized by decreased brain weight, degradation of the cortex, enlarged ventricles, and pronounced neuronal loss in the hippocampus

ACh treatment for Alzheimer’s disease

prevents the degradation enzyme acetylcholinesterase from functioning effectively to allow acetylcholine to accumulate in the synapse

Anti-amyloid antibody infusion therapy

anti-amyloid antibodies are used to remove amyloid from the body and brain so that plaques do not form or stay in the body, which has proved to not be needed long term

Biological rhythm

inherent rhythm that controls or initiates various biological processes like sleep

Circadian rhythm

daily/24 hour rhythm that governs the human sleep-wake cycle

Free running cycles

human sleep cycle that extends to about 25-27 hours when all external influences are removed

Biological clock

internal, neural system that times behavior, is entrained by Zeitgebers, and is located in the suprachiasmatic nucleus (SCN) in the hypothalamus

Pineal gland

produces melatonin into the bloodstream, which promotes sleep

Role of Blue light in sleep

causes the retina to send projections to the hypothalamus directing the pineal gland to stop releasing melatonin, making it harder to sleep (produced by technology screens and the sun)

Non-24-Hour Sleep Wake Disorder

circadian rhythm disorder that is common in blind people due to their lack of environmental cues indicating time, causing difficulty sleeping at night and increased drive to sleep during the day

Non-24-Hour Sleep Wake Disorder treatment

use of melatonin receptor agonist that activates melatonin receptors proficiently

Non-REM stage 1

drowsiness, low EEG frequency

Non-REM stage 2

EEG shows higher amplitude and lower frequency with addition of sleep spindles

Non-REM stage 3

moderate to deep sleep, EEG shows even higher amplitude and lower frequency

Non-REM stage 4

deepest, slow wave sleep with highest amplitude and lowest frequency shown on EEG

REM sleep

rapid eye movement sleep, categorized by paralysis of large muscle groups, dreaming, restoration and EEG similar to that of waking (dominant in last 4 hours of sleep)

Non-REM sleep

slow, rolling eye movement sleep where night terrors, sleep walking/talking, and tossing/turning takes place (dominant in first 4 hours of sleep)

Effects of sleep deprivation

includes microsleeps, hallucinations, and impaired memory and learning