ap psychology unit 1

Heredity

the passing of traits genetically from one generation to another

Nature vs. Nurture

Are we a product of our genes or our environment or both?

Central Nervous System (CNS)

• Consists of the brain and spinal cord

• all about decision making

Peripheral Nervous System (PNS)

• gathers info and sends signals from CNS to the rest of the body

• consists of sensory and motor neurons that extend and connect to the CNS

Somatic Nervous System

• part of the PNS

• controls skeletal muscles

• voluntary movement

Autonomic Nervous System

• glandular activity, heartbeat, digestion

• part of the PNS

• consists of the sympathetic and parasympathetic nervous systems

Sympathetic Nervous System

• arouses and spends energy

• fight or flight

• accelerate heartbeat, raise blood pressure, slow digestion, raise blood sugar, sweat

Parasympathetic Nervous System

• calms you

• conserve energy

Neuron

• nerve cell, building block of nervous system

Dendrite

• branching extensions from the neuron that receive messages → neural impulse

Cell Body (Soma)

• part of neuron that has the nucleus, keeps the cell alive

Axon

• neural extension that passes messages through its branches to other neurons or to muscles or glands

Axon Terminal

• branches from the axon that form junctions with other cells

Myelin Sheath

• fat tissue layer that encases the axon

• speeds up transmission as neural impulses hop from one node to the next

Sensory Neurons

• neurons that carry incoming information from the body’s tissues and sensory receptors to the brain and spinal cord

• afferent

Interneurons

• neurons within the brain and spinal cord

• communicate internally and process info between sensory inputs and motor outputs

Motor Neurons

• carry info from the brain and spinal cord to muscles and glands

• efferent

Glial Cells

• cells in the nervous system that support, nourish, and protect neurons

• help with learning, thinking, memory

• produce myelin

Resting Potential

Resting Potential

• neuron normally has a negative inside charge and a positive outside charge

Threshold

• the level of stimulation required to trigger a neural impulse

Action Potential

• a neural impulse; a brief electrical charge that travels down an axon

• neuron sends message → action potential → ion exchange through K/Na pumps → depolarization (cell becomes more positive) → repolarization → negative→hyperpolarization (too negative, refractory period)→resting potential

All-or-None Principle

• a neuron is either firing with full intensity or not firing at all

Depolarization

• neuron fires → axon lets in positive sodium ions → no charge difference between inside/outside → next axon channels open → domino effect

Refractory Period

• brief resting pause that occurs after a neuron has fired

• neuron must return to resting state before more action potentials

Synapse

• junction between axon terminal of a sending neuron and the dendrites of receiving neuron

• action potential → axon → neurotransmitters→synapse→other receptors on other neuron

Neurotransmitter

• chemical messenger that crosses the synapse

• influence whether receiving neuron will generate a neural impulse

Excitatory

• neural signals that cause an action potential

• if excitatory > inhibitory → threshold reached → action potential

Inhibitory

• neural signals that stop an action potential

Reuptake

• neurons absorb excess neurotransmitters from the synapse

Agonist

• molecule that increases neurotransmitter action

• increase production, bind to receptors

Antagonist

• molecule that blocks or inhibits neurotransmitter action

Reuptake Inhibitor

• some antidepressant meds block reuptake of mood-enhancing neurotransmitters

• drug that does exactly what the name says

• acts as an agonist

GABA (gamma-aminobutyric acid)

• major inhibitory neurotransmitter

• Malfunction →seizures, tremors, insomnia (low levels)

Glutamate

• major excitatory neurotransmitter

• involved in memory

• Malfunction→migraines or seizures (high levels)

Acetylcholine (ACh)

• Involved in muscle action, learning, and memory

• Malfunction→Alzheimer’s disease: ACh-producing neurons deteriorate

Dopamine

• neurotransmitter that affects movement, learning, attention, and emotion

• Malfunction →Parkinson’s disease (low levels); Schizophrenia (high levels)

Serotonin

• neurotransmitter that affects mood, hunger, sleep, and arousal

• Malfunction→Depression (low levels); anxiety disorders (low levels)

Norepinephrine

• neurotransmitter that helps control alertness and arousal

• basic level of alertness

• Malfunction→Depression (low levels); anxiety (high levels)

Endorphins

• neurotransmitters that influence perception of pain and pleasure

• natural opiates

• Malfunction → Opiate addiction (overuse of endorphin-like drugs)

Substance P

• neurotransmitter that influences pain, mood, stress

• Malfunction → chronic pain (high levels), vomiting (high levels), Inflammatory diseases (high levels)

Endocrine System

• glands that secrete hormones into the bloodstream

• slower than neurotransmitters

Hormones

• chemical messengers that travel through blood stream

Hypothalamus

• a part of the Limbic System

• responsible for bodily maintenance - eating, drinking, body temp

• homeostasis

• reward centers

• also controls pituitary gland and suprachiasmatic nucleus

• sleep-wake cycle

Pituitary Gland

• most influential endocrine system gland

• regulates growth and controls other endocrine glands

• releases hormones

Adrenaline (Epinephrine)

• Danger → ANS → adrenal glands → epinephrine and norepinephrine

• increase heart rate, blood, pressure, blood sugar

• fight or flight

• hormones still linger after a while

Ghrelin

• hormone produced by stomach that stimulates appetite

• also stimulates pituitary gland to release growth hormone

Leptin

• hormone produced by fat cells

• reduces hunger and appetite

• increases metabolism

Melatonin

• hormone produced in pineal gland

• regulates sleep-wake cycle

• makes you sleepy

Oxytocin

• neurotransmitter and hormone

• enables contractions associated with birthing, milk flow, sex

• promotes pair bonding, group cohesion, trust

• Malfunction → difficulty in social bonding (low levels)

Hindbrain

• major region of the brain

• includes the brainstem and cerebellum

Brainstem

• located near spinal cord

• oldest and innermost region of brain - automatic survival functions

• contains the medulla and pons

• left-right wiring

Medulla

• base of brainstem

• controls heartbeat and breathing

Pons

• above medulla

• coordinate movements and sleep

Reticular Activating System (RAS)

• controlled by the reticular formation

  • network of neurons that travels through brainstem to thalamus

  • filters stimuli and relays info to other brain areas

  • multitasking

• Arousal, wakefulness, alertness

• receives sensory input from body and determines what info is important enough to bring to conscious attention

Cerebellum

• located at the rear of the brainstem

• processes sensory input, coordinates movement output and balance, nonverbal learning and memory

• judge time, modulate emotions

• nondeclarative memories

Forebrain

• major region of the brain

• contains the cerebrum and cerebral cortex and basal ganglia

• also contains the thalamus, hypothalamus, and pineal gland

Thalamus

• on top of medulla 

• sensory control center

• receives info on all senses except smell

• sends info to higher brain regions

• receives some higher brain replies which it sends to medulla and cerebellum

Limbic System

• neural system that includes the amygdala, hypothalamus, hippocampus

• associated with emotions and drives

Amygdala

• neural clusters in the Limbic System

• aggression and fear; emotion

Hippocampus

• neural center

• processes conscious, explicit memories; declarative memories

• decreases as we grow older

Cerebrum

• the two cerebral hemispheres

• 85% of the brain

• important brain functions - thinking, planning, reasoning, language, sensory interpretation

Cerebral Cortex

• covers the cerebrum

• ultimate control and information processing center

Corpus Callosum

• band of neural fibers connecting the two brain hemispheres and carrying messages between them

Hemispheric Specialization

• Right Hemisphere - perceptual task, inferences, copying drawings, faces, emotion, modulate speech, self-awareness

• Left Hemisphere - speaking/mathematics, language

Contralateral Organization

• left side of brain controls the right side of the body

• right side of brain controls the left side of the body

Frontal Lobe

• just behind the forehead

• speaking, muscle movements

• plans, judgements, executive functioning

• reasoning, social understanding, learning

Prefrontal Cortex

• association area

• enables judgement, planning, new memories

• personality

Motor Cortex

• back of frontal lobe

• controls voluntary movements

Broca’s Area

• speaking

• left frontal lobe

Parietal Lobe

• top of head and toward the rear

• receives sensory input for touch and body position

• mathematical and spatial reasoning

• self-perception, sensory integration, learned movements, location awareness

Somatosensory Cortex

• area at front of parietal lobes that registers and processes body touch and movement sensations

• more sensitive body areas have greater somatosensory are devoted to it

Occipital Lobe

• back of the head; receive information from visual fields: visual cortex

• spatial processing, color processing, depth perception, face recognition

Temporal Lobe

• above the ears

• auditory areas - receiving information from the opposite ear

• auditory cortex

• Lobe contains hippocampus, Wernicke’s area, amygdala

• sight and sound, visual recognition

Wernicke’s Area

• language understanding

Phineas Gage

• lost part of frontal lobe in railroad accident

• changed personality and lost executive functioning skills

Split-Brain Research

• when the corpus callosum was severed → can separate right and left hemispheres

• the left hemisphere can say what image it had seen while the right hemisphere can’t

• the right hemisphere can point to what it had seen with the left hand

• the left hemisphere sees what’s on the right side of view while the right hemisphere sees what’s on the left side of view

Brain Plasticity

• the brain’s ability to change by reorganizing or building new pathways

• practice → brain develops differently

• Severed brain and spinal cord neurons do not regenerate

• some brain functions seem preassigned to specific areas

• blindness or deafness can make unused brain available for use

  • reassignment

• Neurogenesis - new neurons, master stem cells

EEG (electro encephalogram)

• an amplified recording of the waves of electrical activity sweeping across the brain’s surface

• electrodes on scalp

CT/CAT Scan (computed tomography)

• X-ray photographs taken from different angles and combined by a computer into a composite representation of brain structure

• structural scan

MRI (magnetic resonance imaging)

• put head in strong magnetic field which aligns spinning atoms of brain

• radio wave pulse disorients atoms

• when atoms return to normal spin they emit signals that show detailed picture

• structural 

fMRI (functional MRI)

• show function and structure

• bloodflow in MRI scans compared to show activity

• functional

PET Scan (positron emission tomography)

• display of where radioactive glucose goes when brain does a task

• functional

Consciousness

• our subjective awareness of ourselves and our environment

• arises from synchronized activity across the brain

• strong stimulus → brain-wide coordinated activity → consciousness

• weak stimulus → local activity that fades

• Dual Processing - info is simultaneously processed consciously and unconsciously

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

    • different brain areas can let you perceive

• Parallel processing

  • processing many aspects of a problem simultaneously - well learned info or easy problems

• Sequential processing

  • processing one aspect of a problem at a time - new info or hard problems

Circadian Rhythms

• Sleep-Wake Cycle

  • the suprachiasmatic nucleus regulates circadian rhythm with sunlight

  • Eyes→Optic chiasm→suprachiasmatic nucleus→visual cortex and pineal gland→melatonin

  • Light outside→pineal gland stops releasing melatonin

  • Dark outside→melatonin released

Optic Chiasm

• relays visual info from the eyes to the visual cortex in the occipital lobe

• suprachiasmatic nucleus receives info from optic chiasm to determine sunlight or darkness

REM Sleep

• not deep sleep, very wakeful

• very active brain

• body paralyzed, muscle atonia

  • sleep paralysis - you wake up but are unable to move body

    • →hallucinate

• Dreams, sleep talking

• important for memory

Non REM Sleep

• Nonrem stage 1 - just beginning to sleep

• Nonrem stage 2 - sleep spindles: bursts of brain activity

• Deep Sleep - slow wave sleep, Nonrem 3, 4

  • sleep walking - neurological miswiring

  • Benefits: restorative to body and immune system

• more deep sleep at the start of sleep and less near the end

Dream Theories

Freud

• dreams are a form of wish fulfillment

• express guilt or trauma

• unconscious workings of brain

Information Processing

• dreams help sort out day’s events and consolidate memories

Physiological Function

• regular brain stimulation from REM may help develop or preserve neural pathways

Neural Activation

• REM sleep triggers neural activity that evokes random visual memories which our sleeping brain turns into stories

Sleep Apnea

• can’t properly breath while sleeping → wake up repeatedly

Narcolepsy

• activation of sympathetic nervous system causes people to fall asleep

Insomnia

• can’t sleep, neurotransmitters like norepinephrine at night keep you alert

REM sleep behavior disorder

• body not paralyzed during REM sleep - talking, moving

Transcranial Magnetic Stimulation

• stimulate parts of the brain to move body parts

• depression treatment

• stick electrodes in brain

• what parts of the brain work with the body

Schwann cells

• form the myelin sheath

Nodes of ranvier

• gaps between myelin sheath

Nondeclarative memories

• knowing directions, how to write, how to tie a shoe

• spatial, motor

• classical conditioning

Declarative memories

• Semantic - facts and knowledge

• Episodic - life experiences

Anterograde Amnesia

• can’t form new memories

• Case study HM

Short-term memory

• what are you thinking in real time

• has a limit