AP Psychology: Unit 2 (Biological Bases of Behaviour)

ch. 3 of Myers' Psychology for AP, pp. 51-111 + in-class notes

lesion

selective destruction of tissue

CT scan

x-ray photos that can reveal brain damage

PET scan

depicts brain activity by showing each brain area's glucose use; uses a radiotracer glucose molecule that enters the brain to map activity

MRI

head placed in magnetic field, then atoms disrupted provide a picture

fMRI

reveals functioning and structure through mapping bloodflow in brain areas

electroencephalogram (EEG)

amplified readout of brainwaves

brainstem

the crossover point of the nervous system; spinal cord swells into skull; most primitive part of brain; handles mostly non-voluntary functions

medulla oblongata

top of the spinal cord; swells into the brain; controls essential life functions like heartrate and breathing

pons

bridge between cerebral hemispheres & medulla/cerebellum; controls sleep cycles and coordinates movements

reticular formation

covers brainstem in neurons and carries messages throughout brainstem; handles incoming stimuli and relays the information elsewhere; acts as a filter

thalamus

top of brainstem; receives information from all senses besides smell; routes it and sends responses to cerebellum

cerebellum

the “little brain”; processes sencory input; coordinates fluid movement, balance, and posture

limbic system

border between the brain’s older parts & cerebral hemispehere; aids with emotions, hunger, and the formation of memories

amygdala

influences aggression & fear; handles fight or flight

hypothalamus

located below thalamus; governs bodily maintenance; hormones activated trigger the pituitary gland; monitors blood chemistry

hippocampus

plays role in memory storage & formation; connects emotions to memories

cerebral cortex

thin surface layer of neural cells - info processing centre; “grey matter”; handles consciousness and thought; has folds for increased surface area

glial cells

act as “glue”; worker cells provide for neurons; provides nutrients insulating myelin, guides connection.

frontal lobe

handles speaking, movement, and judgement; contains motor and sensory cortex; located at the front/top part of the brain

prefrontal cortex

part of frontal lobe; handles complex cognitive behaviours, personality, social behaviour, and decision making

motor cortex

movement portion of frontal lobe; at rear of frontal lobe and controls voluntary movement

sensory cortex

part of the frontal lobe; receives incoming information for processing

parietal lobe

handles sensory input from touch and body; located at top/rear of the brain

somatosensory cortex

part of parietal lobe; responsible for receiving and processing sensory information from entire body

occipital lobe

processes information from eyes; located at back of brain

visual association cortex

part of occipital lobe; handles recognition of lines, angles, shapes, and movements

temporal lobe

processes auditory information; located above the ears

association area

part of brain not involved in primary motor/sensory functions; difficult to map; can link memories with sensory input

aphasia

impairment of language

broca’s area

association area in the left frontal lobe that directs muscle movement for speech

wernicke’s area

association area in the left temporal lobe; responsible for language comprehension and expression

angular gyrus

part of brain involved in reading aloud

neuroplasticity

brain’s ability to modify structure of itself, especially during childhood, by recognising damage

neurogenesis

formation of new neurons

corpus callosum

wide band of axons connecting the two hemispheres in the brain; can be split to alleviate seizures

phrenology

popular but ill-fated research that supposedly could identify mental abilities based on skull bumps

neuron

nerve cell; building block of nervous system

sensory neuron

handles incoming information; carries information from sensory receptors to the brain

motor neuron

handles outgoing information; carries information from brain to muscles

interneurons

carries internal information between motor and sensory neurons

dendrite

bushy bit of a neuron that receives messages and controls impulses

axon

extension of a neuron; terminal branches of axon forms junctions with other neurons; carries information away from a cell

cell body / soma synapse

cell’s life support; can reject messages from the dendrites from going through the axon

axon

passes messages away from cell body; can be covered by myelin sheaths for increased speed

neural impulse

electrical signal that travels down the axon to the terminus

myelin sheath

fatty sheath that covers axon of some neurons and speeds up impulses

terminus

creates junctions with other cells at terminal buttons

action potential

charge on an axon

excitatory vs. inhibitory

excitatory accelerates signals, inhibitory slows signals

all-or-none principle

neural impulses are never partially fired; either completely or not at all

synapse

gap between two different cell’s terminus and dendrite; messages sent across this gap

neurotransmitter

chemical sent between neurons

reuptake

process by which neurotransmitters are reabsorbed by the neuron that sent the message

selectively permeable membrane

cell membrane allows only certain ions to pass through

resting potential

difference between the charges inside and outside the neuron; primed and ready to fire in this state

refractory period

period of time where the cell cannot reach full action potential; about 1 millisecond in length

acetylcholine (ACh)

neurotransmitter responsible for muscle action, learning, and memory

dopamine

neurotransmitter responsible for movement, learning, and attention

serotonin

neurotransmitter responsible for mood, hunger, sleep, and arousal

norepinephrine

neurotransmitter responsible for alertness and arousal

gamma aminobutyric acid (GABA)

neurotransmitter responsible for inhibition of signals

glutamate

neurotransmitter responsible for excitatory signals

endorphin

“endogenous morphine”; helps with pain control

agonist neurotransmitter

transmitter that will still trigger the cell despite not being an exact match

antagonist neurotransmitter

transmitter that inhibits the triggering of the cell by blocking the receptor site

nervous system

electrochemical communication network within the human body; made up of the central nervous system (CNS) and peripheral nervous system (PNS)

central nervous system (CNS)

part of the nervous system made up of the brain and spinal cord

peripheral nervous system (PNS)

part of nervous system responsible for communicating with the body; receives signals from central nervous system and dispatches them throughout body

somatic nervous system

part of the peripheral nervous system responsible for voluntary control of skeletal muscles

reflex arc

signal from sensory organ to spinal cord that is processed in the spinal cord instead of the brain

autonomic nervous system

part of the peripheral nervous system responsible for controlling glands & muscles of internal organs automatically; made up of sympathetic and parasympathetic nervous systems

sympathetic nervous system

part of autonomic nervous system responsible for arousal and using energy; opposed with parasympathetic nervous system

parasympathetic nervous system

part of autonomic nervous system responsible for the conservation of energy and relaxation; opposed with sympathetic nervous system

endocrine system

hormonal communication system that communicates with neurons; sends hormones through bloodstream; tends to work slower than nervous system

pituitary gland

area controlled by hypothalamus in the brain that releases hormones responsible for growth, blood pressure, and energy management; a master gland

behaviour genetics

study of relative power of genes & environment on behaviour

genome

the shared blueprint that makes us human; the vast majority of it is shared between each person; only a few differences in it determine variations in people

biological psychology

focus on importance of genes and biological influences on psychology

heredity

the sum of all biological processes by which characteristics are inherited

gene

segment of DNA that make the body’s blueprint

epigenetics

study of heritable changes in gene expression (active vs. inactive)

sensitive period

for some behaviours or physical characteristics different environments are important at different times for the expression of genes

monozygotic twins

identical; one fertilised egg that splits; same gender and genetically identical

dizygotic twins

fraternal; two separately fertilised eggs; effectively same as siblings, just born simultaneously

heritability

the extent to which differences in traits across groups of people can be accounted for by differences in genes; how much the difference is due to genes

interaction

effects of the environment on certain genes

molecular genetics

study of the molecular structure of genes

natural selection

traits predisposed to survival will be passed on to future generations

mutation

random change to genes

psychological adaptation

development or change of a mechanism in a mind; can be anything from how food tastes to the habitat one lives in