AP psychology

AP psychology

Biological bases of behavior

  • Prenology:

    • 1800- Franz Gall suggested bumps in the skull represented mental abilities (shape of brain)
    • Incorrect theory
    • Thinking brain works like a muscle

  • Biological psych:

    • Links between biology and behavior

  • We are a biopsychological system

  • Humans and animals operate similarly when processing information

  • The neuron:

    • Based on electrical impulses
    • Same features as other cells
    • Nucleus
    • Cytoplasm
    • Cell membrane

  • Cell body: soma

  • Dendrites: receive messages from other neurons

  • Axon: send messages to other neurons, muscles, glands

  • Axon terminal branches/buttons: where messages are sent out

  • Myelin sheath: fatty substance that covers to speed up neurotransmission, insulates

  • Dendrite –> axon

  • Glial cells: create myelin sheath, remove waste in brain, insulate and support neurons

    • Schwann: insulate neurons
    • Astrocytes: provide nutrition to neurons
    • Oligodendrocytes: insulate neurons

  • Membrane is depolarizing

  • Resting potential: neuron is not transmitting info, its resting

    • Outside is positive
    • Inside is negative

  • Action potential

    • Neural impulse
    • Brief electrical charge that travels down the axon
    • Caused by movement of positively charged ions

  • Sodium potassium pumps:

    • Pump positive ions out from the inside of the neuron
    • Kicks ions back on
    • Makes ready for an action potential

  • All or none response: when depolarizing current exceeds the firing threshold/absolute threshold, a neuron will fire

  • Axons surface is selectively permeable - things can travel through

  • Action potential properties:

    • When depolarizing current exceeds the firing/absolute threshold the neuron will fire
    • If threshold fails, neuron will not fire
    • Intensity of action potential: of an action potential remains the same throughout the length of the axon.
    • Refractory Period: After a neuron fires an action potential it pauses for a short period to recharge itself to fire again.
    • resting potential : how polarized it is in resting state
    • action potential: peak
    • Know how to label graph

  • Synapse: junction between axon tip of a sending neuron & dendrite/cell body of receiving neuron

    • The gap is called the synaptic cleft

  • Neurotransmitters: chemicals released from the sending neuron that travels across the synapse and bind to receptor sites on the receiving neuron

    • How neurons communicate
    • Live in vesicles

  • Reuptake: neurotransmitters in synapse are reabsorbed into the sending neurons (presynaptic membrane)

    • Involved in refractory period

Steps:

  1. action potential causes vesicles to open
  2. Neurotransmitter released into synapse
  3. Locks onto receptor molecule in the postsynaptic membrane
  4. Neurotransmitter reuptake in vesicles
  • Lock & key

2 categories of neurotransmitters

  1. Excitatory: fire

    1. Key fits and opens receiving neuron –> leads to firing
    2. Causes depolarization of membrane and orimites action potential in receiving neuron

  2. Inhibitory: don’t fire

    1. Activation of receptor leads to hyperpolarization and stops action potential

Know what a neurotransmitter is and what happens if you have too much or too little

  • Major neurotransmitter:
    • Acetylcholine:
    • Excitatory
    • Function: motor movement & memory
    • Undersupply: alzheimers, paralysis
    • Dopamine:
    • Excitatory & inhibitory
    • Function: motor movement, alertness, pleasure
    • Undersupply: parkinson's disease
    • Oversupply: schizophrenia
    • Gaba:
    • Most common inhibitory neurotransmitter (tells to stop)
    • Undersupply: huntington’s disease, anxiety, insomnia, epilepsy
    • Glutamate:
    • Most common excitatory neurotransmitter
    • Memory
    • Oversupply: ALS, migraines, seizures
    • Endorphins:
    • Inhibitory
    • Alleviate pain
    • Similar to opioids
    • Undersupply: chronic pain disorders
    • Serotonin:
    • Inhibitory
    • Sleep, mood, appetite, sensory
    • Undersupply: depression
    • Oversupply: anxiety, limits depression
    • Substance P
    • P is pain
    • Responsible for sending pain messages
    • Norepinephrine:
    • Excitatory
    • Alertness & arousal
    • Hormone
    • Undersupply: depression

SSRI

Selective serotonin reuptake inhibitors

  • Boots serotonin connections by blocking reuptake of serotonin
  • mirror neurons:
    • Fire when someone else does something
  • Nervous and endocrine system
    • central nervous system: brain and spinal cord
    • peripheral nervous system: autonomic & simatic
  • Nerves:
    • Bundles of axons together
    • peripheral nervous system
    • Connect CNS to muscles, sense organs, glands
  • Sensory (afferent) neurons
    • Input from sensory organs to the brain & spinal cord
  • Motor (efferent) neurons
    • Output from brain and spinal cord to muscles and clans
  • Effector cells
    • Respond to stimuli at end of neuron
  • Interneurons
    • Carry info between brain and spinal cord
  • SAME
    • Sensory afferent motor efferent
  • autonomic nervous system:
    • Involuntary
    • Regulates functions of internal organs
    • Regulates involuntary responses
    • Ex: heart beat
  • Somatic nervous system
    • Voluntary
    • Connects brain to motor neurons
    • Were in control of this system
  • sympathetic nervous system
    • fight or flight
  • CNS
    • Brain
    • Sensation
    • Movement
    • Info processing
    • Spinal cord
    • Reflexes
    • communication between brain and peripheral nervous system
  • Endocrine system:
    • Body's slow chemical communication system
    • Communication carried out by hormones
    • Hormones -slow in blood
    • Neurotransmitters- fast in the synapse
  • Hormones
    • Mood
    • Metabolism
    • Energy
    • Muscles
  • endocrine system:
    • Hypothalamus:
    • controls pituitary gland
    • Thyroid gland:
    • metabolism
    • pituitary gland:
    • secretes hormones,
    • master gland
    • Controlled by hypothalamus
    • parathyroid glands:
    • regulate level of calcium in blood
    • Adrenal glands:
    • fight or flight
    • Pancreas:
    • blood sugar
    • Ovaries & testes:
    • sex hormones
    • Quiz up to endocrine/hormones
    • Everything before
    • Neuron and parts and functions
    • neurotransmitters

The Brain:

  • Lesion: where you experimentally destroy brain tissue (in animals) to study behavior
  • Autopsy: post-mortem study of brain to compare changes
  • Clinical observation: watching people & their behavior

Ways to view the brain:

  • EEG: electrodes are put on ones scalp
    • Tells about brain activity
  • CT scan: a series of x rays
    • Structural
  • PET scan: tells function of brain by inserting radioactive glucose
  • MRI: uses magnetic fields and radio waves to make an image
    • Structural
  • fMRI: reveals brain functioning

Hindbrain:

  • Brainstem: oldest part of brain, where spinal cord enters skull
    • Medulla: basic functioning and reflexes
    • Pons: sleep & wake cycle
  • Reticular formation: alertness & attention
  • Cerebellum: balance, movement, learning
  • Thalamus: sensory except smell

Limbic System:

  • Hippocampus
    • Formation of memories
    • Damage to it → alzeimers
    • ex) HM
      • Had hippocampus removed due to seizures
      • Lost memory and couldn't make new memories
  • Amygdala
    • Emotions of fear and aggression
    • Decision making
  • Hypothalamus
    • Below thalamus
    • 4 Fs
    • Fight
    • Flight
    • Feeding
    • Fornicating
    • Controls endocrine system
    • Body temperature
    • Melatonin release
    • Ventromedial hypothalamus (VMH)
      • Suppress hunger
    • lateral hypothalamus
      • Increases hunger
  • Associated with emotions, aggression, sex drive, memory

Reward Center

  • Reward deficiency syndrome: people are genetically predisposed to crave whatever provides missing pleasure. `

Cerebral Cortex

  • Interconnected neural cells that cover cerebral hemispheres
    • Control & info processing center
    • Frontal lobe
    • Decision making
    • Planning
    • Movement
    • Parietal lobes
    • Sensory cortex
      • Touch
      • Taste
    • occipital lobe
    • Visual
    • temporal lobe
    • Auditory
    • Facial recognition
    • Smell
  • Motor cortex:
    • Controls voluntary movements
  • Somatosensory cortex:
    • Registers body sensations, touch, temperature, pain

The Brain

  • Plasticity- brain's ability to modify itself after injury/illness
  • Neurogenesis- formation of new neurons in adulthood (from sleep, exercise, non-stress environment) stem cells
  • Long term potentiation- the more you use a neural pathway the stronger it becomes
  • Neural networks- interconnected neural cells
  • Splitting the brain- a procedure where 2 brain hemispheres are separated by cutting corpus callosum
  • Nature v nurture
  • Chromosomes: contain genes
  • Human genome: common human dna sequence
  • Genotype: genetic info
  • Phenotype: physical traits

Association areas

  • Areas of cerebral cortex not involved in primary motor or sensory functions
  • Higher mental functions

Language:

  • Aphasia: impairment of language
    • Caused by damage to left hemisphere
  • Wernicke's area: impaired understanding

Twin & Adoption Studies:

  • Molecular genetics:
    • How specific genes influence behavior
  • Heritability:
    • Population of variation among individuals that can be attributed to genes
    • Varies for traits
    • Heritability estimates only reflect what causes variation in traits.
    • Estimates the sources of differences among people
    • Not inherited
  • Epigenetics: how the environment triggers gene expression
  • Epigenetic marker: organic methyl which if attached to dna, proteins will not be encoded
    • Either says make protein or stop making it

Sleep & dreaming

  • Stages of sleep:
    • 1: nonREM
    • Light sleep
    • hallucinations
    • 2: nonREM
    • Sleep spindles
    • Largest amount of sleep
    • 3&4: nonREM
    • Deep sleep
    • 5: REM = rapid eye movement
    • Active brain
    • Elevated heart rate & blood pressure
    • Body is paralyzed
    • Sympathetic NS action
    • Dreaming
    • Rem deprivation → rem rebound
  • Micro sleep:
    • Tiny second long sleeps
  • Circadian rhythms:
    • Internal biological clock
    • Governs sleep and wake cycle
    • Influences pineal gland (secretes melatonin)
  • circadian rhythm: biological clock
  • Insomnia: increases ghrelin and cortisol
  • Dream theories