AP Psychology - Unit 2: Biological Basis of Behavior

nature-nurture issue

nurture works on what nature bestows

genes

biochemical units of heredity that make up chromosomes

environment

surrounds/influences your behavior

behavior genetics

study of relative power and limits of genetics on behavior

genome

biological blueprints in cell nucleus to build biological structures/processes

chromosomes

specific DNA structures containing genes

DNA

double helix molecule of genes

Nucleotides

A, T, C, G nucleotide structures that make up DNA

identical twins

monozygotic; from single fertilized egg; genetically identical

fraternal twins

dizygotic; different fertilized eggs; genetically different

molecular genetics

the study of the molecular structures and functions of genes and how they play a role on our behavior

heritability

how much does variance between individuals come from genetic differences

epigenetics

study of how the surroundings express/unexpress genes without changing DNA

evolutionary psychology

study of evolution of behavior of mind under the lens of natural selection

introverts are quiet and do not draw attention -> lions do not eat people they do not know exist -> introverts survive to modern day

charles darwin

"on the origin of species"

natural selection

evolutionary process; genes passed on by those who survive to reproduce

mutation

random errors in gene replication that change genetic code; source of diversity

nucleus

contains chromosomes -> DNA -> genes -> nucleotides

twin studies

compare fraternal (shared womb space and living environment) and identical (share DNA) twins to study nature v nurture

genetically influenced traits

extro/introversion
temperament
neuroticism
divorce rate
abilities
fears

environmentally influenced traits

values
beliefs
manners

predisposition

unexpressed genes with possibility of expression

What is the endocrine system

slower to act than the nervous system; produces hormones via glands that circulate bloodstream

what are the components of the endocrine system and their functions

pineal gland: secretes melatonin/sleep patterns
hypothalamus: governs via pituitary gland
pituitary gland: master gland
thyroid gland: hormones to regulate metabolism
parathyroid gland: regulate blood calcium
thymus: immune system
adrenal gland: secretes (nor)epinephrine when stressed
pancreas: regulate blood sugar
ovary: secrete estrogen
testies: secrete testosterone

hormones

chemical messengers

HPA Axis

Hypothalamus, Pituitary gland, Adrenal gland
bodily response to stress

nervous system

electrochemical communication system which receives, transfers, sends info

CNS components

brain, spinal cord

PNS definition and components

sensory/motor neurons connect CNS to body

somatic nervous system
autonomic nervous system

somatic nervous system

control/voluntary muscle movement

autonomic nervous system function and components

autonomous

controls glands/internal organ functions

sympathetic nervous system
parasympathetic nervous system

sympathetic nervous system

mobilize body for fight/flight stress
heart beat
glucose rush

parasympathetic nervous system

calm; conserve energy; rest/digest

neuron

building blocks of the nervous system

parts of the neuron

nucleus; soma; dendrites; myelin sheath; axon; axon terminal

function of dendrites

receives messages from other cells; covered in receptors

function of soma

messages build up, reach threshold, then release

function of axon

messages pass form soma to other neurons/muscle/glands

function of myelin sheath

fatty tissue insulates axon to speed up message transfer

function of axon terminal

forms junctions with other cells
contains vesicles to release neurotransmitters into synapse/dendrite receptors (converted from chemical to electrical signals)

Afferent neurons

detect stimuli, carry info to CNS

Efferent neurons

carry info out of CNS to muscles

Interneurons

connect sensory/motor neurons in CNS

reflex neurons

skips CNS and directly connects efferent and afferent neurons

Describe the transmission of neural signals

resting potential: waiting, no incoming signal, - inside/ + outside

info build

reaching threshold: enough messages received

action potential: sends electrical charge along axon, depolarizes + inside/ - outside, neurotransmitters released into the synapse and bind to receptors of post-synaptic neuron

refractory period: brief period it can't fire impulse, reestablish resting potential conditions

All or Nothing response

neuron either fires full force, or does not

reuptake

the reabsorption by a neuron of a neurotransmitter following the transmission of a nerve impulse across a synapse

eg: axon terminal releases dopamine, it binds to receptors, is released and returns to pre-synaptic axon terminal

acetylcholine ACh

In the somatic nervous system

muscle action
learning
memory

less ACh in those with alzheimer's

Dopamine

learning
attention, emotion

excess associated with schizophrenia

Serotonin

hunger
sleep
arousal
mood

low levels associated with depression

Norepinephrine

arousal and vigilance

GABA

inhibits action potential
anxiety
intoxication

Endorphins

pain reduction
reward

Types of neurotransmitters

Acetylcholine, dopamine, serotonin, norepinephrine, BAGA, endorphins

agonist

mimic neurotransmitters, tricks synapse into thinking receptors are filled, boosts effects of neurotransmitters

antagonist

blocks neurotransmitters from binding with receptors

What is the function of the brainstem and what are its components?

automatic survival functions (breathing, swallowing, vomiting)

Medulla
Pons
Thalamus
Reticular Formation
Cerebellum

Medulla

survival functions, death if damaged, heartbeat

Pons

regulates wakefulness/sleep

reticular formation

arousal and nerve network, coma if damaged

Thalamus

sensory switchboard except smell
smell triggers memory
distributes sensory info

cerebellum

coordinates voluntary movement and balance, muscle memory

Limbic system function and components

emotions

Amygdala, Hypothalamus, Hippocampus

Amygdala

processes emotions, anger, fear, aggression

Hippocampus

attach memories to emotions, processes memories

Hypothalamus

maintenance activity, governs endocrine system via pituitary gland

cerebral cortex and components

information processing, connected to limbic system to reason and emotions factor into decisions

frontal lobe
parietal lobe
motor cortex
somatosensory cortex
occipital lobe
temporal lobe

Frontal Lobe

planning/judgement, includes motor cortex

Parietal Lobe

sensory information

Motor Cortex

voluntary movement and intricate movement

Somatosensory cortex

processing body sensations/touch

occipital lobe

primary visual processing center

temporal lobe

auditory processing lobe

Glial cells

guides neural connections, provides insulating myelin and cleans up ions/neurotransmitters

Association areas

integrate information for higher mental function;
associate senses with memories

Plasticity

ability to change/reorganize pathways after damage

Neurogenesis

formation of new neurons

Broca's area

left frontal lobe; directs muscle movement in speech and expressive language

Wernicke's area

left temporal lobe; language comprehension and receptive language

Lesion

brain tissue destruction to study animal behavior afterwards

What are structure scans? What are some examples?

brain anatomy

CT: x-ray photographs at different angles integrated into single slice image

MRI: magnetic field and radio waves to create computer generated image to distinguish soft tissue AND anatomy

What are function scans? What are some examples?

brain activity/functionality

PET: visual display of brain activity via radioactive glucose in bloodstream

EEG: recording of brain waves from eclectic activity (action potentials) that sweeps brain surface

fMRI: identifies brain region engaged during performance of specific activities

Psychoactive Drug

chemical alters perception/mood via stimulating/mimicking/inhibiting neurotransmitters

Tolerance/ Neuroadaptation

reduced drug effect from regular use as brain produces less to compensate for artificially induced amount

addiction

compulsive craving despite consequences

withdrawal

discomfort following discont. of drug

physical vs psychological dependence

physical: physical withdrawal symptoms due to change in bodily functions
psych: dependence to relieve negative emotions

Define depressants and provide examples

slows neural activity and bodily functions

alcohol: lower self awareness and guilt; inhibitant agonist and glutamate antagonist

barbiturates: lower anxiety and slower CNS

Opiates/heroin: less endorphins; agonist for inhabitants and dopamine

Define stimulants and provide examples

excites bodily functions

cocaine: blocks reuptake of dopamine; dopamine antagonist

ecstasy: triggers release of dopamine/serotonin, blocks reuptake; agonist for serotonin and dopamine

meth: more energy and neural activity; dopamine agonist

Define hallucinogens and provide examples

distort perception, evokes sensations in absence of stimuli

LSD: powerful hallucinations; serotonin agonist

Marijuana: mild hallucinogen, distortion of time; antagonist for inhibitants and dopamine

corpus callosum

large band of neural fibers connecting brain hemispheres

laterlization

specialization of right/left cerebral hemispheres

left hemisphere responsibilities

controls right hand/side
speech
writing
reading
math
logic
analysis
details

right hemisphere responsibilities

left side
non verbal
visual-spacial perception
music/art
emotional thought
big picture
facial recognition

Split Brain procedure

isolates hemispheres by cutting corpus callosum, done to those with severe epileptic seizures