unit 2

a nerve cell, the basic building block of the nervous system

the part of a nueron containing the nucleus

a neuron's often bushy, branching extensions that receive and integrate messages, conducting impulses toward the cell body

the neuron extension that passes messages to other neurons or muscleslands

a fatty tissue layer segmentally encasing the axons of SOME neurons (enables faster transmission speeds)

degeneration of the sheath leads to multiple sclerosis (as the communication to muscles slows, eventual loss of muscle control occurs)

cells in the nervous system that support, nourish, and protect neurons (also play a role in thinking, learning, memory)

(a neural impulse) a brief electric charge that travels down an ions AKA: depolarization

resting potential (-70mV), NTs enter the cell and charge rises, -55mV is the threshold of excitation, the NA+ channelss open and NA+ flood into the cell until it reaches the axom potential, the Na+/K+ pump bring in 2K+ for every 3NA+ that leave the neuron, overshoot the resting potential and then reset before firing again

speed up the neurons

slow down the neurons

the level of stimulation required to trigger a neural impulse

the time after a nueron fires where it returns to its resting state

axon either fires full strength or not at all

terminal button, synaptic space, dendrites

the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron

the gap in the synapse

sacs in the terminal button that release chemicals into the synaptic space

chemical messengers released by synaptic vesicles, bind to receptor sites

nuerotransmitter reabsorbed by the receiving neuron

muscle movement and memory
liked to Alzheimer's (too little)

reward and initiation of movement
linked to Huntington's Disease (too much) and Parkinson's Disease (too little)

mood
linked to major depression (too little)

alertness and arousal
linked to ADHD (too much)

natural, opiate-like neurotransmitters linked to pain contol and pleasure
think: runner's high, accupuncture

the brain needs to balance itself so it lowers is natural opiates and then they are gone when the drugs are gone

a molecule that increases a neurotransmitter's action

a molecule that inhibits/ blocks a nuerotransmitter's action

electrochemical communication network, fast, NTs in the nuerons

chemical communication network, slow, hormones in the bloodstream

brain and spinal chord
descision making

sensory/motor neurons connecting the CNS to the rest of the body

bundles of axons that form neural cables connecting the CNS to muscles/ glands/ sense organs

afferent
carrying incoming info from the tissues/sensory receptors to the brain/spinal chord

efferent
carrying outgoing information from the brain/spinal chord to the muscleslands

neurons within the brain and spinal chord
communicate internally, process info between sensory and motor outputs

voluntary control of skeletal muscles (rest+digest)

controls glands and internal organs' muscles
automatic responses (fight, flight, freeze, fuck)

arousal (mobilizing energy)

calming (conserving energy)

86 million

2 way information highway connecting the peripheral nervous system and the brain
neural fibers- up: sensory info down: motor control info

simple automatic responses to a sensory stimulus

no pain or pleasure, total paralyzation from the neck down

chemical messengers made by the endocrine glands, affect other tissues, influence our interest (sex, food, agression, etc.)

a pair of endocrine glands above the kidneys
seccrete hormones (epinephrine and norepinephrine) that help arouse the body in times of stress

regulates growth and controls other endocrine glands

brain tissue destruction

amplified recording of eletrical brain waves across the brains surface
observes the whole brain in action through its electrical waves

brain imaging through measuring magnetic fields from the brain's natural electical activity
analyze speed/strength to see how certain tasks affect brain activity

x-ray photos used to reveal brain damage

visual display of brain activity (radioactive form of glucose goes where when doing a given task)

brain anatomy through magnetic fields and radio waves

reveals bloodflow (brain activity) by comparing successive MRI scans

between the spinal chord and the brain
automatic survival functions

base of the brainstem
heartbeat and breathing

from the spinal chord through the thalamus
filters stimuli/ relays important info to other brain areas, controls arousal

on top of the brainstem
sensory control center (info from all senses except smell to the brain)

back of the brainstem
sensoy input, coordinates movementalance, non-verbal learning/skill memory

above the medulla
coordination of movement, sleep

below the cerebral hemispheres
amygdala, hypothalamus, hippocampus
emotions and drives

2 lima-bean sized neural clustes
linked to emotion

below the thalamus
maintaining a homeostatic internal state, linked to emotion and reward

neural center that decreases in size/function with age
process and store conscious memories of facts/events

2 cerebral hemispheres
specialized work teams enabling thinking, perceiving, speaking

thin suface layer of interconnected neural cells covering the hemispheres
control and information processing center

folds in the tissue separating lobes

front of the head
speaking, muscle movements, making plans/judgements

middle top
receives sensory input for touch and body position

back of the head
receive info from visual fields

above the ears
auditory areas (info from the opposite ear)

rear of the frontal lobes
controls voluntary movements

front of the parietal lobes
registers/processes body touch and movement sensations

more sensitive=larger area

areas of the cerebral cortex involved in higher mental functions (thinking, learning, memory, speaking)

enables judgement, planning, and processing new memories

altered personality, removal of inhibitions, inability to stray away from violence

language expression (muscle movements involved in speech(
damage affects speaking

language comprehension and expression
damage disrupts cohesive talking and understanding

the brain's ability to change, especially during childhood, by reorganizing after damage or by building new pathways based on experience (strongest in childhood)

the formation of new neurons

severed brain and spinal chord neurons do not regenerate
some brain functions seem preassigned to specific areas

makes unused brain areas available for other uses

the left and right hemispheres of the brain serve different functions

the large band of neural fibers connecting the 2 brain hemispheres and carrying messages between them

sugery cutting the corpus callosum that stops communication between the 2 sides of the brain

speaking, math calculations, processing language, quick literal interpretations of language

making inferences, modulation of speech, self-awareness

subjective awareness of ourselves and our environment

interdisciplinary study of the brain activity linked with cognition (relating specific brain states to conscious experiences

information is often simultaneously processed on separate conscious and unconscious tracks

a condition where a person can respond to a visual stimulus without consciously experiencing it

(unconscious) processing many aspects of a problem simultaneously
process well-learned info or solve easy problems

(conscious) processing one aspect of a problem at a time
process new info or solve hard problems

the study of the relative power and limits of genetic and environmental influences on behavior, determine which genes contribute to specific traits

the genetic transfer of characteristics from parent to offspring (nature)

non-genetic influences (nurture)

threadlike structures made of DNA models that contain genes
46 (23 from each parent)

deoxyribonucleic acid
molecule containing genetic information

units of heredity that make up the chromosomes, segments of DNA that synthesize proteins

expressed
turned on by environmental factors: provide the code to create protein molecules

the complete instructions for making an organism, consisting of all the genetic material in the chromosomes

monozygotic
fertilized egg that splits into 2 (genetically identical)

dizygotic
separate fertilized eggs (same genetic similarity as siblings)

extraversion (outgoingness) and neuroticism (emotional instability)

first researcher to study twins reares apart
found they were alike in personality, intelligence, heart rate, brain waves, and vocal intonations

the proportion of variation among individuals in a group attributed to genes

effect of one factor (environment) depends on another (heredity)

the study of how the structure and function of genes interact with out environment to influence behavior

the study of environmental influences on gene expression that occur without a DNA change

genes react, they don't lead to the same result each time

environmental factors: diet, drugs, stress

what makes humans alike, the evolution of behavior/the mind using principles of natural selection

Charles Darwin
inherited traits that help survival are more likely to be passed down (certain biological/ behavioral variations increase reproductive and survival chances in their environment- these are more likely to be inherited by future generations

random errors in gene replication that lead to a change

common human genetic profile
similarities come from this shared description

women have more at stake (AKA pregnancy)

traits that convey health or fertility (smooth skin, youthful shape)

start with an effect and works backwards
unproductive to compare today's behavior with ancestors
socially unhelpful

a culturally modeled guide for how to act in various situations

genes form us, but other things can shape/change us

a periodic, natural loss of consciousness

internal biological clock: bodies sync with the 24 hour cycle of day and night
altered by age and experience
impacts: sleep/wake, temperature, hormonal, digestive (cycles)

alert and awake
fast frequency, low amplitude, irregular pattern

relaxed and drowsy
fast frequency, low(ish) amplitude, regular pattern

1-7 minutes
drifiting thoughts/images
sensations of falling or floating
leg and arm jerks (hypnagogic sensations)
theta waves present

20 minutes
body relaces, decrease in muscle tension, body temp, heart rate
sleep spindles: bursts of rapid rhythmic brain activity

30 minutes
slow-wave sleep
large slow delta waves
hardest to awaken

15-45 minutes (increases with each cycle)
vivid dreams
paradoxical sleep: muscles are relaxed but other body systems are active
rise in heart rate, rapid irregular breathing, eyes darting around

a pair of cell clusters in the hypothalamus that controls circadian rhythm
responds to light and causes the pineal gland to adjust melatonin secretion

sleep protects, sleep helps us recuperate, sleep helps restore/ build fading memories from the day, sleep feeds creative thinking, sleep supports growth

increases ghrelin (hunger hormone) and decreases leptin (hunger supression hormone)
decreases metabolic rate
increases cortisol (stress hormone that stimulates fat making) production
enhances limbic brain responses to the signal of food and decreases cortical responses for resisting temptation

we sleep to boost our immune cells

ongoing difficulty falling or staying asleep
effects: chronic tiredness, reliance on sleeping pills or alcohol

sudden attacks of overwhelming tiredness (REM sleep)
effects: risk of falling asleep at a dangerous moment

stopping breathing repeatedly while sleeping
effects: fatigue and depression (associated with obesity)

doing normal waking activities while asleep
walking: NREM-3, talking: any tage

appearing terrified, talking nonsense, sitting up or walking during NREM-3
effects: doubled heart and breathing rates

REM
sequence of images, emotions, and thoughts passing through a sleeping prerson's mind

symbolic and remembered parts of a dream

unconscious drives and underlying meanings of a dream

Sigmund Freud
dreams exist to satisfy our wishes
dreams can be analyzed to find unconscious desires

dreams exist to file away memories
dreams help sort through and organize the events of the day

dreams exist to develop/preserve neural pathways
dreams are periods of stimulation that protect and expand the brain's neural pathways

dreams exist to make sense of neural static
the brain dreams in an attempt to bring reason to random activity

dreams exist to reflect cognitive development
dreams are a part of maturing a brain, become more complex with age

chemical substances that alter perceptions and moods

continued substance craving/ use despite significant life disruption/phsyical risk

brain chemistry adapts to counteract the constant effects of a drug, need more of the substance to get the previous effect

craving the drug despite knowing the consequences

the discomfort and distress that follow discontinuing a drug/ behavior

depressant
initial high followed by relaxation and disinhibition
depression, memory loss, organ damage, impaired reactions

depressant
rush of euphoria, relief from pain
depressed physiology, agonizing withdrawl

stimulant
increased alertness and wakefulness
anxiety, restlessness, insomnis, uncomfortable withdrawl

stimulant
euphoria, alertness, energy
irritability, insomnia, hypertension, seizures

stimulant
rush of euphoria, confidence, energy
cardiovascular stress, suspiciousness, depressive crash

stimulant
arousal and relaxation, sense of well-being
heart disease, cancer (from tars)

mild-hallucinogen
enhanced sensation, relief of pain, distortion of time, relaxation
disrupted memory, lung damage(from smoke)

hallucinogen
euphoria, disinhibition
brain damage, depression, fatigue