UNIT 1 AP PSYCHOLOGY

KEY IDEAS: Parts of the brain like the cerebellum, medulla, etc… types of brain test, agonist, antagonist 

• Biological psychologists study the link between biological activity and psychological events 

• Nerve cells conduct electricity and communicate through chemical messages 

• Humans are biopsychosocial systems: cells, organs, body systems + family, community, culture 

• Neurons: nerve cell, basic building block 

  • cell body 

  • axon (they “speak” by passing messages away from the cell)

  • dendrites (they “listen” by receiving messages)

  • Myelin sheath: encase an axon, layer of fatty tissue providing insulation and speed 

• Franz Gall: early 1800s German physician

  • Proposed phrenology (studying bumps on the skull) and could reveal a person’s mental abilities and character traits; false ideology but helped focus attention on localization of function 

    • Localization of function is the idea that various brain regions have particular functions 

• Glial cells: cell in nervous system that support, nourish and protect neurons 

• Action potential: brief electrical charge that travels down an axon 

  • positive outside the cell and negative inside the cell → this is the resting potential

  • Axon surface is semi permeable

  • Depolarizes: opens the gates so positively charged sodium ions flood through membrane thus depolarizing that section and causing a chain reaction 

  • Threshold: level of stimulation needed for an action potential (this occurs when there are more excitatory signals over inhibitory) 

    • Excitatory signals: push the neuron to speed up 

    • Inhibitory signals: pushing the brake 

  • refractory period: resting pause when neuron pumps sodium back outside, needed for the neuron to fire again 

  • All-or-none response: increase level of stimulation does not increase neural impulse intensity 

    • Strong stimulus can trigger more neurons to fire so therefore will detect more intensity, but the intensity is the result of the chain reaction 

  • Synapse: junction between axon tip of sending neuron and dendrites of receiving neuron

  • Neurotransmitters: chemical messengers that cross synaptic gap between neurons and bind to receptor sits on receiving neuron 

    • Reuptake: sending neuron absorbs excess neurotransmitters 

• Acetylcholine (ACh) - muscle action, learning, and memory

• Dopamine: movement, learning, attention, and emotion; oversupply linked to schizophrenia

• Serotonin: mood, hunger, sleep and arousal; undersupply linked to depression 

  • Antidepressant drugs raise serotonin levels 

• Norepinephrine: alertness, arousal; undersupply can depress mood 

• GABA: inhibitory neurotransmitter; undersupply linked to seizures, tremor, insomnia 

• Glutamate: excitatory neurotransmitter, memory

• Endorphins: “morphine within” linked to pain and pleasure, body’s natural neurotransmitters

• Agonist: binds to receptor and mimic effect of neurotransmitter 

• antagonist: block neurotransmitter

• CNS: brain and spinal cord; peripheral nervous system: nerves 

• Sensory neurons: carry messages from body tissue inward to brain and spinal cord

• motor neurons: carry messages from CNS out to muscles/glands

• Interneurons: within brain and spinal cord. Communicate internally between motor and sensory neurons 

• Simple spinal reflex pathway includes a sensory neuron, a motor neuron, and a interneuron 

• Spinal cord connects peripheral nerves and the brain; if severed, then you can not feel pain in the paralyzed body 

• Endocrine system: slow communication system full of glands that secrete hormones, messages are slower than the nervous system but the effects tend to last longer 

• endocrine system is controlled by the hypothalamus

• pituitary gland: growth hormone and oxytocin (birthing, milk flow, group bonding, social trust) 

  • Master gland, it controls the release of other hormones 

• Lesion: tissue destruction in the brain

• electroencephalogram/EEG: amplified recording of brain waves through use of electricity 

• Magnetoencephalography: measuring magnetic fields, used to pinpoint epilepsy 

• CT scan: x rays

• PET scan: tracks radioactive glucose to discover brian function and use 

• MRI: radio plus disrupts atoms and when atoms return it shows a detailed image of soft tissue 

• fMRI: reveal brain function and structure by tracing blood flow 

• CT and MRI show anatomy; EEG, PET, MRI reveal brain function 

• Hindbrain: medulla. pons, cerebellum, directs essential survival like breathing 

• Midbrain: atop the brainstem connecting the hindbrain with forebrain, controls motor movement and transmits auditory and vision information 

• Brainstem: crossover point for nerves from each side of the brian to connect

• Medulla: heartbeat and breathing 

• Pons is above medulla and helps coordinate movement 

• Reticular formation: enables arousal, awakeness

• Thalamus: sensory control center, receives info except for smell 

• Cerebellum: coordination and balance 

• Limbic system: amygdala, hypothalamus, hippocampus 

  • Amygdala: emotion, rage, fear

  • Hypothalamus: hunger, thirst, body temp, sexual behavior; referred to as the reward center because of the Olds + Milner electrodes in rats 

  • Hippocampus: conscious memories 

• Cerebrum: 2 hemispheres, perceiving, thinking, and speaking 

• Cerebral cortex: cover cerebrum; larger cortex = increased capabilities 

• frontal lobe: personality, making plans, judgment, muscle movement 

  • Motor cortex: voluntary movement 

• Somatosensory cortex: behind motor cortex, receiving info from skin and movement of body parts

• Parietal lobe: touch and body position 

• Occipital lobe: visual 

• Temporal lobe: auditory 

• Areas requiring precise control occupy greatest amount of cortical space 

• Association areas: higher mental functions, remembering, thinking, speaking 

  • They wont trigger an observable response, they can not be neatly mapped 

  • Remember faces, math and spatial reasoning 

• Broca's area: left hemisphere; “speaking”

• Wernicke: language comprehension and expression, “understanding”

• Plasticity: brain ability to change and reorganize after damage 

  • Strongest in childhood 

• Neurogenesis: brain mending itself by producing new brain cells

• Lateralization is the idea that the left and right hemisphere look alike but serve very different functions

• Vogel and Bogen -  speculated that major epileptic seizures were caused by amplification of abnormal brain activity between the two hemispheres as it bounced back and forth

• corpus callosum is the neural fibers connecting two hemispheres and sending messages between them

  •  split brain is a surgery that isolates the two hemispheres by severing the corpus callosum

• Right brain: making inferences, modulate our speech, make meaning clear, sense of self

• left brain:  control speech, make quick literal interpretations of language

• dual processing: information is often simultaneously processed on separate conscious and unconscious tracks

• Blindsight is acting as of a person can see; they can't consciously recognize objects but they can grasp and navigate them

• sequential processing involves being skilled to solving new problems which require or focused attention

  • parallel processing is unconscious behavior that is faster than sequential processing

•  visual perception track: lets us recognize things and plan future actions

•  visual action track: guides our movement

• Identical twins are single fertilized egg that splits into two and they are typically of the same sex versus fraternal twins that are separate eggs that share a fetal environment

• Thomas Bouchard was the first researcher to study twins reared apart;  despite separation he found that the voices, personality, intelligence, heart rate, etc. were virtually similar between the twins 

  • Criticisms of his studies: the plural of an anecdote is not data

• Adopted children are influenced by their adoptive parents through their attitudes, values, manners, faith, politics but typically not their personalities

• interaction is the interplay that occurs when the effect of one factor (environment)  depends on another (heritability)

•  molecular behavior genetics is a subfield of biology that studies molecular structure and function of genes

• heritability is the proportion of variation among individuals that we can attribute to genes;  differences among people

  • Heritability increases as differences due to environment decrease

• epigenetics is the study of environmental influences on gene expression that can occur without a DNA change