AP Psychology: Unit 1

Biological Bases of Matter, States of Consciousness, Sensation

Genetic Predisposition

Increased chance of developing a specific trait or condition due to our genetic code.

Determines sex

23rd Pair of Chromosomes

Turner’s Syndrome (Abnormality)

Single X chromosome in the 23rd pair

Turner’s Syndrome

Short stature, webbed necks, differences in physical sexual development.

Klinefelter’s Syndrome (Abnormality)

Extra X chromosome, XXY pattern

Klinefelter’s Syndrome

Minimal sexual development and personality traits like extreme introversion.

Down Syndrome (Abnormality)

Extra chromosome on the 21st pair

Down Syndrome

Rounded face, shorter fingers and toes, slanted eyes set far apart and some degree of intellectual disability.

Neuroanatomy

Study of the parts and functions of neurons

Neurons

Individual nerve cells

Dendrites

Root-like parts of the cell which stretch out from the cell body, grow to make synaptic connections with other neurons

Cell Body/Soma

Contains the nucleus and other parts of the cell needed to sustain its life

Axon

Wirelike structure ending in the terminal buttons that extend from the cell body.

Myelin Sheath

A fatty covering around the axon of some neurons that speeds neural impulses.

Multiple sclerosis

Myelin sheath deteriorates around neurons, interfering with neural transmission. Symptoms of muscle weakness, coordination problems and fatigue

Terminal Buttons

The branched end of the axon that contain neurotransmitters.

Neurotransmitters

Chemicals in terminal buttons to allow neurons to communicate. Neurotransmitters fit into receptor sites on the dendrites of neurons like a key fits into a lock.

Synapse

The space between the terminal buttons of one neuron and the dendrites of the next neuron.

Neurotransmission

All the parts of a neuron work in a sequence to transmit a message.

Resting State/Potential

Neuron has an overall slightly negative charge (-70mV) because mostly negative ions are within the cell and positive ions are surrounding it. Cell membrane is selectively permeable to maintain this difference in charge.

Threshold

Once enough neurotransmitters are received, cell membrane becomes permeable. All the positive ions rush into the cell bringing the charge to around +40mV. The change in charge spreads down the entire length.

Action Potential

The change in charge spreads down the length of the neuron at a speed of 120m/s.

All-or-none Principle

A neuron cannot fire a little or a lot, if dendrites receive enough to push the neuron past the threshold it will fire, and if not it won’t.

Depolarization (also known as neural firing)

Cell fires due to the resting potential of the cell, the negative charge becoming depolarised when positive ions rush in, changing the charge from overall negative to positive.

Excitatory Neurotransmitters

Excite the next cell into firing

Inhibitory Neurotransmitters

Inhibit the next cell from firing

Dopamine

Motor movement, alertness, attention, emotions, movement learning

Parkinson’s

Lack of dopamine

Schizophrenia

Excess dopamine

Serotonin

Mood control, hunger, sleep, arousal

Clinical Depression

Lack of serotonin

Norepinephrine

Alertness, arousal, increases blood pressure/heart rate, helps with fight-or-flight response

Depression

Lack of norepinephrine

Glutamate

Excitatory, memory, long-term memory, learning

Glutamate (problems)

Migraine, seizures

GABA

Important inhibitory, sleep, movement, slows down nervous system

GABA (Problems)

Internalises during seizures, sleep problems

Endorphins

Pain control, pain tolerance

Endorphins (Problem)

Involved in addictions

Substance P

Pain perception, transmitting pain signals from sensory neurons to CNS

Lack of pain perception

Lack of Substance P

Acetylcholine

Motor movement, muscle action, learning, memory

Acetylcholine (Problem)

Myasthenia gravis (muscle weakness)

Alzheimer’s

Lack of Acetylcholine

Sensory/Afferent Neurons

Body to brain

Interneurons/Association Neurons

Take the messages and send elsewhere

Motor/Efferent Neurons

Brain to body

Central Nervous System

Consists of brain and spinal chord, nerves encased in bone, the body’s decision maker

Peripheral Nervous System

all nerves not encased in bone, transmits decisions of CNS

Somatic Nervous System

Controls voluntary muscle movements

Autonomic Nervous System

Controls involuntary functions (heart, lungs, internal organs etc.), stress responses such as the fight-or-flight response, operates autonomously

Sympathetic Nervous System

Mobilizes/arouses our body to respond to stress, accelerates heart rate, blood pressure, breathing but slows digestion to conserve energy

Parasympathetic Nervous System

Calms our body’s response to stress, return to homeostasis, counteracts parasympathetic nervous system

Glial Cells (Glia)

Cells in the nervous system that support, nourish and protect neurons; may also play a role in learning, thinking and memory. Structure, insulation, communication, waste transportation.

Refractory Period

a brief resting pause that occurs after a neuron has fired; subsequent action potentials cannot occur until the axon returns to its resting state

Reuptake

a neurotransmitter’s reabsorption by the sending neuron

Endocrine System

System of glands that secrete hormones, controlled by hypothalamus

Hormones

Chemical messengers manufactured by the endocrine glands, travel through bloodstream and affect other tissues

Adrenaline

Activated during fight or flight in stressful situations, speeds up bodily processes

Adrenal Glands

Produce adrenaline/epinephrine

Leptin

Involved in weight regulation, suppresses hunger (food less appetizing)

Ghrelin

Motivates eating/increases hunger (food more appetizing), growth hormone

Melatonin

Triggers sleep and wakefulness responses in brain, pineal gland, circadian rhythms

Oxytocin

Promotes good feelings such as trust and bonding, produced in hypothalamus and released in pituitary gland

Phineas Gage Accident

Experienced damage to the front part of the brain and doctors documented changes in behaviour and personality after the accident. Changes in emotional control, became highly emotional and impulsive.

Lesioning

Removal or destruction of part of the brain

Frontal Lobotomy

Historically used to control mentally ill patients who had no other treatment options

Electroencephalogram (EEG)

Detects brain waves, used in sleep research to identify the different stages of sleep and dreaming

Computerized Axial Tomography (CAT/CT)

Uses several x-ray cameras which rotate around the brain to create a 3D image, only shows structure not function (eg. good to identify tumour)

Magnetic Resonance Imaging (MRI)

Similar to CAT (gives a picture), more detailed images because of different technology, only shows structure not function

Positron Emission Tomography (PET)

See what areas of the brain are most active, how much of a certain chemical (eg. glucose) parts of the brain are using, more glucose = higher activity, higher activity = warm reds and oranges, lower activity = cool blues and greens

Functional MRI (fMRI)

Combines MRI and PET, can show details of brain structure with info about blood flowing brain, tying brain structure to activity

Hindbrain

Life support system, controls the basic biological functions which keep us alive

Medulla

Control of blood pressure, heart rate and breathing

Pons

Control of facial expressions

Cerebellum

Coordinates habitual muscle movements

Midbrain

Coordinates simple movements with sensory information

Reticular Formation

Netlike collection of cells that controls body arousal and attention, if fails body goes into a deep coma

Forebrain

Responsible for thoughts and reason

Thalamus

Receives sensory signals coming up spinal cord and sending them to appropriate areas of the forebrain

Hypothalamus

Controls metabolic functions: body temperature, sexual arousal/libido, hunger, thirst, endocrine system, biological rhythms (being a morning/night person)

Amygdala

Experiences of emotion

Hippocampus

Memory system

Cerebral Cortex

As we grow up the neurons connect making our brain faster

Left Hemisphere

Gets sensory messages, controls motor functions of right side of the body, more verbal

Right Hemisphere

Gets sensory messages, controls motor functions of left side of the body, visual perception and making inferences, modulate speech, orchestrate self-awareness

Association Area

Any area not associated with sensory info/muscle movements, active thoughts, responsible for judgement and humour

Prefrontal Cortex

Directs thought processes, “central exec,” important in predicting consequences, pursuing goals, emotional control and engaging in abstract thought

Broca’s Area

Controlling muscles involved in producing speech, damage can result in aphasia

Wernicke’s Area

Linguistic processing via written and spoken speech, damage would affect ability to understand, still seem fluent but issues with grammar and syntax

Motor Cortex

Signals to muscles, control voluntary movement, top controls toes bottom controls head

Somatosensory Cortex

Receives incoming touch sensations, top controls toes bottom controls head

Phantom Limb Syndrome

If an individual loses a part they may still perceive sensations due to the mapping of sensory cortex

Occipital Lobes

Interpret messages from our eyes in visual cortex

Visual Cortex

Impulses are sent from retina for interpretation, impulses for right half of retina are processed in the visual cortex of right occipital lobe and same for left

Temporal Lobes

Process sound sensed by ears, processed by ears then turned into neural impulses then interpreted auditory cortices

Brain Plasticity

Brain’s flexibility, compensation level for damage (especially while young)

Conscious

Information that you are currently aware of (about yourself and environment)

Non-conscious

Body processes controlled by the mind that we aren’t aware of (heartbeat, respiration)

Pre-conscious

Information you aren’t currently thinking about (memories)