AP Psych Unit 1

1.1: Nature vs. Nurture 

  • Nature comes from our parents and determines many basic characteristics

    • Physical traits

    • Predispositions to abilities and behaviors 

    • Intelligence and personality 

  • Nurture is how our environment influences us and our development. Works alongside Nature to influence how we are

    • Family dynamics or parenting styles

    • Education

    • Cultural context or social interactions

    • Personal experiences

  • Evolutionary psychology focuses on natural selection and how it influences behaviors and mental processes. 

    • Why certain behavioral tendencies persist over human populations 

  • Rosenzweig's study on brain development on rats

    • He raised genetically similar rats in different environments to determine the effect on neural development. 

    • Impoverished rats had fewer neural branches.



1.2: Overview of the Nervous System 

  • The Spinal cord and the Brain are part of the Central Nervous System 

    • The spinal cord carries messages to and from the brain 

  • Nerves that are not encased in bones are part of the Peripheral Nervous System 

    • Carries sensory information to the CNS and motor information from the CNS

    • The Somatic Nervous System receives messages from the motor cortex and controls voluntary movements

    • The Autonomic Nervous System carries out automatic vital functions such as breathing, blinking, and heart rate 

      • The Sympathetic Nervous System controls the response to stressful events

      • The Parasympathetic Nervous System controls the response after the stressful events and brings the body back to homeostasis and slows down or speeds up necessary body functions 




1.3: The Neuron and Neural Firing


  • Neurons are responsible for carrying messages through electrical impulses 

  • Glial cells provide physical and chemical support for the neurons 

  • Afferent/ Sensory Neurons: take information from the senses to the brain

  • Interneurons: take information to different parts of the body 

  • Efferent/ Motor Neurons: take information from the CNS to the PNS to initiate action

  • Neural firing is an electrochemical process

    • Resting potential: the neuron is charged and ready to fire

    • Threshold: when the neuron reaches this level, it activates and fires

    • Action potential: when the neuron fires. All or nothing

    • Refractory: resting period as the neuron recharges to fire again 

  • Neurotransmitters: chemical messengers between the neurons 

    • Excitatory and inhibitory neurotransmitters

    • Agonists block reuptake and excites SSRIs. Forces them to stay in the synapse and repeatedly fire. 

    • Antagonists: block receptors of neurotransmitters or block receptor sites 

  • Acetylcholine: voluntary movement, muscle contractions, and learning

    • Excess: depression 

    • Deficit: dementia/ alzheimer’s

  • Dopamine: movement, attention, and rewards

    • Excess: schizophrenia 

    • Deficit: parkinson’s 

  • GABA: Inhibits excitation and anxiety 

    • Excess: seizures, insomnia

    • Deficit: anxiety 

  • Endorphins: pain relief, pleasure, and natural opiates 

    • Deficit: Addictions 

  • Serotonin: Mood regulation and hunger

    • Deficit: depression, anxiety, and OCD

  • Epinephrine: fight and flight responses

    • Excess: High blood pressure 

    • Deficit: depression 

  • Norepinephrine: return to homeostasis

    • Excess: schizophrenia

    • Deficit: depression 

  • Glutamate: the link between neurons and learning 

    • Excess: overstimulation 

  • Substance P: pain perception, stress reliever response 

    • Excess: eczema and emotional problems 

    • Deficit: alzheimer's and type 1 diabetes 

  • Alcohol: Inhibits GABA and Glutamate, causing a prolonged calm- depressant (agonist for GABA)

  • Opiates: mimic endorphins for pain relief, and if you rely on this too much, it could reduce the production of natural endorphins- depressant (agonist for endorphins)

  • Cocaine: Rush of euphoria depleting neurotransmitters- stimulant (antagonist for dopamine, serotonin, and norepinephrine)

  • Ecstasy: triggers dopamine and serotonin and blocks reuptake- stimulant 

  • Nicotine: triggers release of neurotransmitters- stimulant 

  • Caffeine blocks adenosine receptors for more alertness- stimulant (antagonist for adenosine)

  • Depressants slow the CNS 

  • Hallucinations distort perception and create a dreamy, relaxed state 



1.4: The Brain


  • Lobes of the Cerebral cortex:

    • Frontal lobe: logic 

    • Parietal lobe: senses

    • Occipital lobe: vision 

    • Temporal lobe: memory

  • Lesions: purposeful destruction of the brain to alleviate symptoms

  • EEG: Measures brain waves based on state of consciousness

  • fMRIs: combines MRI technology and the ability to see blood flow: shows the brain structure and the activity of the brain 

  • Brain plasticity: certain parts of the brain are responsible for certain things, but if it gets damaged, the brain reorganizes itself to take over the function through another part of the brain 

  • Frontal lobe: voluntary movement and executive functions 

  • Motor cortex: thoughts to physical action, muscle coordination

  • Parietal lobe: sensory perception 

  • Sensory cortex: processes information from the senses 

  • Occipital lobe: visual processing area

  • Amygdala: remembering episodic memories, emotional memories 

  • Temporal lobe: auditory information, memory, emotions

  • Auditory cortex: processes speech sounds

  • Wernicke’s Area: language processing

  • Broca’s Area: speech production and articulation 

  • Cerebellum: posture, balance, and movement 

  • Brainstem: breathing, heart rate, blood pressure 

  • Medulla Oblongata: heart rate, blood flow, autonomic nervous system functions 

  • Reticular formation: alertness, pain modulation, expressions, and sleep 

  • Pons: pain sensation, balance, movement, and sleep

  • Visual cortex: visual information receiver and processor

  • Corpus callosum: connects hemispheres, movement, and vision 

  • Thalamus: all sensory nerves, except smell, are processed here 

  •  Hypothalamus: body temperature, hunger, thirst, and mood 

  • Optic nerve: eyes send information to the brain 

  • Pituitary gland: produces and releases hormones

  • Medulla: link the cardiovascular and respiratory systems

  • Olfactory bulb: sends information about smells

  • Hippocampus: memory, learning, and encoding 

  • Prefrontal cortex: cognitive functions 

  • Limbic system: regulates emotions, memories, and behaviors 



1.5: Sleep

  • Natural Circadian Rhythm: sleep-wake cycle that repeats every 24 hours 

  • Stages of Sleep

    • Awake: produces beta waves

    • In the process of falling asleep: produces alpha waves

    • NREM1: happens only once and produces theta waves. Hypnagogic sleep, in which the muscles relax but the brain is still awake

    • NREM2: Slower theta waves with sleep spindle and k-complex 

      • Important for memory consolidation

    • NREM3/4: deepest form of sleep with delta waves 

      • Important for physical and hormonal health 

    • REM: most conscious state and when dreams happen 

  • Activation-synthesis Theory: Dreams are caused by random neural firing, and the cerebral cortex attempts to understand it 

    • Biological theory 

  • Information processing Theory: the brain processes information from the day and moves it to memory 

    • Cognitive theory caused by neurons 

  • REM Rebound: If you miss too much REM sleep, the next time you sleep then you will spend more time in that stage, shortening the other stages 

  • Disorders:

    • Insomnia: difficulty falling asleep

    • Narcolepsy: difficulty staying awake

    • Sleep Apnea: breathing randomly stops and starts during sleep 

    • Sleep walking: person walks or does other activities while asleep in NREM stages

    • REM Sleep Behavior Disorder: You act out your dreams, resulting in talking or violent behavior



1.6: Sensation 

  • Collects information from the physical world and sends it to the brain 

  • Uses the process of transduction, which translates physical information into chemical signals 

  • Synesthesia: a special condition in which the senses are connected

    • A certain color might remind you of a smell or of a visual setting 

  • McGurk effect: conflicting stimuli from sound and vision 

  • Absolute threshold: detect stimuli 50% of the time. Goes from nothing to something 

  • Just Noticeable difference: how much change is needed to detect the change in stimuli 

  • Weber’s law: Proportional change needed. The more stimuli it starts with, the more change needed to detect the change. If it starts with less stimuli, there doesn’t need to be a lot of change to detect it 

  • Vision

    • Cones are located in the middle of the fovea/ retina 

      • Rods see black and white, while cones see color 

    • Light travels through the eye by entering the cornea 

    • It moved through the pupil surrounding the iris 

    • Goes through the lens behind the pupil that changes shape to focus images on the retina in a process called accommodation

    • The retina contains rods and cones (peripheral vision has more rods)

    • Transduction begins when the photoreceptors excite the bipolar cells, which send messages to ganglion cells, The axons make optic nerve 

    • Information travels to the thalamus and then occipital lobe where information 

  • Trichromatic theory: red, green, and blue are the main colors, and they mix to create the other colors that we see. Explains color blindness

  • Opponent-process theory: Receptors come in pairs. Blue and yellow, red and green, black and white 

    • Explains after images

  • Deficiencies:

    • Near/Far-sightedness: close objects are clear, but far objects are blurry/ far objects are clear, but close objects are blurry 

    • Color Blindness: inability to distinguish certain colors. Caused by cone problems 

    • Blindsight: People with damage to the visual cortex can respond to visual stimuli without perceiving them 

    • Prosopagnosia: inability to recognize faces

    • Aphasia: damage to Wernicke’s area leading to trouble speaking, understanding and reading, and writing 

  • Hearing:

    • Sound waves enter and travel through the auditory canal to the eardrum, which will begin to vibrate 

    • The vibrations increase as they moves through the ossicles in the order of hammer, anvil, and stirrup 

    • Once it reaches the inner ear, called the oval window, it will burst into the cochlea

    • Motion ripples through the basilar membrane, which lines the cochlea, knocking over hair cells that transduce vibrations to neural signals that are taken by the auditory nerve 

    • The auditory nerve sends signals to the thalamus and then the temporal lobe to the processed by the auditory cortex

  • Place Theory: We hear sounds based on where the cochlea is activated. Pitches stimulate specific parts of the basilar membrane (high pitches)

  • Frequency Theory: Different pitches will cause different amounts of neurons to fire (low pitches)

  • Valley Theory: Neurons work together to produce pitches. The higher the pitch, the more neurons activated 

  • Hearing loss: conduction deafness, usually due to old age. Damage to the vibration process of hearing 

  • Sensorineural deafness: damage to the nerve cells in the cochlea caused by exposure to loud noises 

  • Smell and Taste:

    • Uses chemicals to perceive unlike in waves 

    • Each smell has a different place to bind to in the nose, and it sends a signal to the brain 

    • Taste profiles: sweet, salty, bitter, umami, oleogustus

    • Based on the clustering of pepia: supertaster, medium taster, non taster 

  • Kinesthetic sense: movement and coordination

  • Vestibular sense: balance and body orientation

  • Gate Control Theory: The spinal cord is in charge of how we feel pain 

  • Phantom limb: if we don’t have a body part but the brain still thinks it's there and feels it