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

  1. 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

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