AP Psych - Unit 2: Biological Bases of Behavior

neuron

interconnected information processors made of many parts that work together

Functions/types of neurons

receive sensory info (afferent)

process info and integrate with prior experience (interneurons)

output to guide our actions (efferent)

soma

the cell body of the neuron responsible for maintaining the life of the cell, contains nucleus and branches out into dendrites

dendrites

a neuron's branching extensions that receive messages and conduct impulses toward the cell body and down the axon

axon

the extension of a neuron, ending in branching terminal fibers, through which messages pass to other neurons or to muscles or glands

action potential

electrical signal that travels down the axon

terminal buttons/branches

contain synaptic vesicles that contain neurotransmitters, form junctions with other cells

mylein sheath

a segmental layer of fatty tissue that covers many axons and helps speed neural impulses

synapse

areas where two neurons meet (gap between them)

glial (glia) cells

support neurons (stimulate growth, repair damage, keep them in place)

step by step action potential

dendrites- receive info from other neurons send to soma

if cell depolarizes enough and reaches threshold an action potential fires

impulse moves done axon, vesicles pushed to terminals and releases ntm to synapse

refractory period of rest

refractory period

when the cell is going back to rest (polarized), cannot fire another action potential

all-or-none principle

the law that the neuron either fires an action potential or doesn't

polarized

highly negative charge in the soma (when resting)

depolarized

positive ions go inside when soma gets info,

Neurotransmitters

Chemicals released into synapse that transmit information from one neuron to another, have to fit into a certain receptor (dopamine ntm can only fit into a dopamine receptor

excitatory EPSP

post synaptic neuron fires an action potential (depolarized)

inhibitory IPSP

post synaptic neuron doesn't fire an action potential (polarized)

Reuptake

ntm are recycled by resting neuron (reeled back in)

agonist

mimics an ntm (binds to receptor to activate), prevents reuptake, increases production and release

antagonist

blocks receptor sites, prevents ntm from bonding, decreases production and release

acetylcholine

A neurotransmitter that enables learning and memory and voluntary muscle contraction, used by PNS

acetylcholine deficiency

alzheimer's disease

dopamine

experience of pleasure (reward pathway), initiation of voluntary muscle movement

dopamine deficiency and excess

d: parkinsons

e: schizophrenia, addiction

norepinephrine

arousal, alertness, attention, used by SNS, associated with mood

norepinephrine deficiency

d: depression, anxiety

serotonin

mood, sleep, appetite,

serotonin deficiency and excess and fluctuation

d:depression

e:mania

f:BPD

GABA

inhibitory (don't fire) reduce CNS, involved in sleep and arousal

GABA deficiency

d: huntington's disease

Glutamate

excitatory (keep firing), strengthens neural connections, learning, doing things faster with less focus,

endorphins

reduce pain, euphoria,

peripheral nervous system

sensory and motor neurons that connect CNS to rest of your body; relay between brain, spine and rest of body

autonomic nervous system

controls involuntary functions that happen automatically in the body

sympathetic nervous system

part of the autonomic nervous system that arouses the body, mobilizing its energy in stressful situations, fight or flight, increases heart and breathing rate

parasympathetic nervous system

part of the autonomic nervous system that calms the body, conserving its energy, rest and digest, decreases heart and breathing rate,

somatic nervous system

controls voluntary movements of skeletal muscles, and communication to sense organs

afferent neurons (sensory neurons)

neurons that TAKE IN information from the senses to the CNS, feelings and senses (skin and eyes)

efferent neurons (motor neurons)

neurons that take information from the brain to the rest of the body CARRY OUT INFO from CNS to PNS, guide our actions

central nervous system

contains spine and brain, controls most functions of the body and mind, processes, interprets and stores info, issues orders to muscles, glands, and organs

brain

The mass of nerve tissue that is the main control center of the nervous system

spinal cord

Nerves that run up and down the length of the back and transmit most messages between the body and brain VIA INTERNEURONS

reflex/reflex arc

reflex: quick involuntary responses, only conrolled by spine

RA: afferent neurons bring in sensory input to spine, spine makes efferent neurons have reaction, then info goes to the brain and pain is felt

EEG

monitoring electrical activity of the brain (brain waves) by attaching electrodes on the scalp, non invasive procedures, done for sleep studies

CT/CAT

Imaging technique where a computer coordinates and integrates multiple X-rays of a given area, x-ray of brain structure CANNOT SEE TISSUE (horizontal slice, many angles put together) ex: see tumors and broken bones, appendectomy

PET

Involves injecting individuals with radioactive glucose and monitoring chemical activity in different areas of brain (will ask to do tasks to see which areas are activated/blood goes to) ex: criminals may be mad at seeing bunnies when normal people would be happy

MRI

Magnetic fields and radio waves map out brain structure SHOWS TISSUE ex: ligaments in knee

fMRI

Monitors blood flow and oxygen in the brain to identify areas of high activity when patients are engaged in a certain behavior or task

Lesioning

Destroying a small part of brain tissue, electrodes used to burn tissue and disable structure NOT USED ON HUMANS (unless to sever corpus callosum for seizures) mostly rats for research very invasive procedure

ESB

Deep brain stimulation activates a brain structure with weak electric currents sent to an implanted electrode very invasive ex: increase dopamine to help Parkinsons

TMS

Temporary enhancement or depression of activity in a specific area of the brain using a magnetic coil on a small paddle non-invasive

Hindbrain

Primitive Brain: Medulla, Pons, Cerebellum, Reticular Formation

Medulla

vital functions (HR BP breathing)

Pons

sleep and dreams (REM sleep), should be stimulated at night

cerebellum

balance and coordination

Reticular formation

network of cells control alertness, attention, and arousal

locus coeruleus

nucleus within RF, stress and panic responses

Substantia Nigra and striatum

initiation of movement has lots of dopamine receptors

Forebrain

Thalamus, hypothalamus, limbic system

LImbic system

emotion center: contains hippocampus and amygdala

thalamus

"Central relay station" for all senses except smell, afferent neurons go here and then to another lobe to process information

hypothalamus

Biological drives ex: hunger, thirst, body temperature, sleep

hippocampus

Formation of new memories, creates memories, does not store them, not responsible for recall

amygdala

Emotional reactions especially fear and aggression

AP ONLY basal ganglia

Important to smooth muscle movement and actions works with cerebellum involved in procedural memories for skills

Cerebrum/Cerebral Cortex

Controls Complex Thought processes, connects left and right hemispheres

Cerebral Hemispheres

Right hemisphere controls left side of body left hemisphere controls right side of body CONTRALATERAL

corpus callosum

bundle of fibers that connect left and right hemispheres, allows halves to communicate

association cortices

allows to communicate, responsible for thought, memory, and learning in combination with forebrain, integration of sensory info puts everything together to make it make sense

occipital lobe

contains visual cortex, seeing

parietal lobe- contains sensory cortex

contains somatosensory cortex (touch pressure pain)

temporal lobe

contains auditory cortex

frontal lobe

motor cortex- movement

prefrontal cortex- higher order thinking (decision making, planning)

mirror neurons

Neurons that fire when we watch others perform actions, brain firing is almost as if we are doing it

neurogenesis

the formation of new neurons

Plasticity

ability of brain to strengthen existing neural connections and form new connections, ability to rewire brain ex: when someone goes blind their hearing is heightened, when brain gets split L and R hemispheres work independently

Right/Left Brain

Cerebral lateralization

L Hemisphere

controls right side, speech and language, logic, analysis, math skills

Brocas Area

located in left frontal lobe, physical production of speech and language

Aphasia and types

aphasia- language deficit due to stroke/brain injury

brocas-Broken speech

wernickes-What are you saying?

Wernicke's area

located in left temporal lobe, comprehension and interpretation of speech and language

R Hemisphere

Controls movement of L side of body; nonverbal, creative/artistic, spatial patterns and facial recognition, emotion- both expressing and reading others

Split Brain Reasearch

split brain=severed/lesioned corpus callosum, R+L hemi can no longer communicate

AP ONLY: study by sperry and gazzaniga

endocrine system

glands that secrete hormones (chemicals) into the bloodstream, and are absorbed by organs and glands throughout the body

hormones

the chemicals released by endocrine glands into the bloodstream

pitutary gland

master gland of endocrine system (in brain)

oxytocin

hormone that regulates reproductive behaviors (trust, bonding, cooperation, empathy, "love" hormone, reduce stress, melt when you get hugged)

chromosomes

strands of DNA that carry genetic info (46 tot)

zygote

fertilized egg (first 2 weeks)- DNA is assembled

genes

DNA segments that carry genetic info

Homozygous vs. Heterozygous

2 of the same genes vs 2 different genes

dominant vs recessive

dominant: only needs one allele to show, overrides the recessive gene, expressed in heterozygous condition

recessive: needs 2 of the same alleles, masked in heterozygous condition, only displayed in homozygous condition

genotype vs phenotype

genotype- genetic makeup

phenotype- what we see, ways in which genotypes are manifested in observable characteristics

polygenic inheritance

characteristics that are influenced by more than one pair of genes (ex. skin color, widows peak is monogenic)

identical (monozygotic) twins

1 fertilized egg that splits (exact same genotype)

fraternal (dizygotic) twins

develop from separate fertilized eggs. They are genetically no closer than ordinary brothers and sisters

genetic mapping

The process of determining the location and chemical sequence of specific genes on specific chromosomes.

epigenetics

study of how genetics are controlled by factors other than DNA, how does nurture affect nature

Darwin

survival of the fittest