AP Psychology - Chapter 2

Phrenology

A popular early 1800s practice that studied bumps on the skull to determine mental abilities and character traits.

Localization of Function

The concept that different brain regions are responsible for specific functions.

Neurons

Neural cells designed to share information electrochemically with other neurons.

Cell Body (Soma)

The nucleus and life support center of a neuron.

Dendrites

Fibers that receive and integrate information, directing it toward the cell body.

Axon

The single lengthy fiber of a neuron that transmits messages to other neurons.

Myelin

A fatty tissue layer that insulates axons and speeds up neural impulses.

Multiple Sclerosis

A condition resulting from the degeneration of the myelin sheath, leading to slowed communication to muscles and loss of muscle control.

Glial Cells

Support cells that provide structure, insulation, communication, and clean up neurotransmitters in the nervous system.

Action Potential

An electrical impulse that a neuron sends down its axon when stimulated.

Excitatory Signals

Neural signals that promote the generation of an action potential.

Inhibitory Signals

Neural signals that regulate the activation of excitatory signals.

Threshold

The minimum intensity at which excitatory signals must exceed inhibitory signals to trigger an action potential.

Synapse

The gap or junction between two neurons where neurotransmitters are released.

Neurotransmitters (NTs)

Specialized biochemical messages that transmit signals across the synapse.

Reuptake

The process of a neurotransmitter being reabsorbed by the sending neuron.

Acetylcholine (ACh)

• A neurotransmitter involved in control of muscles & memory

  • myasthenia gravis is a disorder in which the immune system makes antibodies that block ACh receptor sites - with fewer receptor sites, the muscles receive fewer signals and become weak

Dopamine

• A neurotransmitter involved in reward/pleasure/emotion, motor behavior, & attention

  • Undersupply -> Parkinson's disease

  • Oversupply -> contributes to psychological disorders like Schizophrenia

Serotonin

• A neurotransmitter that regulates sleep, mood, and appetite

• low levels are linked to depression.

Norepinephrine

A neurotransmitter involved in alertness and the "Fight or Flight" response.

Endorphins

Neurotransmitters that have morphine-like effects, providing pain relief and pleasure.

Substance P

A neurotransmitter that transmits pain signals.

GABA (gamma-aminobutyric acid)

• An inhibitory neurotransmitter that promotes tranquility

  • low levels are associated with seizures and insomnia.

Glutamate

• A neurotransmitter involved in learning and memory

  • excess can lead to impulsive behavior

  • overstimulation of the brain and migraines or seizures, which is why some people avoid MSG (monosodium glutamate) in foods

Agonist

A molecule that mimics or increases a neurotransmitter's action.

Antagonist

A molecule that inhibits or blocks a neurotransmitter's action.

Reuptake Inhibitors

• Molecules that attach to an axon, blocking reabsorption

  • build up causes more action potential

Nervous System

The body's electrochemical communication network consisting of the nerve cells of the central and peripheral nervous systems.

Sensory Neurons

Neurons that carry incoming information from the body's tissues and sensory receptors to the brain and spinal cord; also known as afferent neurons.

Motor Neurons

Neurons that carry outgoing information from the brain and spinal cord to the body's muscles and glands; also known as efferent neurons.

Interneurons

Neurons located within the brain and spinal cord that process information between sensory input and motor output.

Central Nervous System (CNS)

The part of the nervous system comprised of the neurons of the brain and spinal cord.

Cerebrospinal Fluid

A fluid that bathes the brain and spinal cord, cushioning them, flushing waste products, and carrying some chemicals.

Neural Networks

Clusters of neurons in the brain that work together to process information.

Reflex

A simple, automatic response to a sensory stimulus.

Reflex Arc

The neural pathway that involves sensory neurons, interneurons in the spinal cord, and motor neurons to produce a reflex action.

Peripheral Nervous System

The part of the nervous system that includes all the other nerves of the body outside the CNS.

Somatic Nervous System

The part of the peripheral nervous system that transmits sensory messages to the CNS and allows voluntary movement.

Autonomic Nervous System

The part of the peripheral nervous system that regulates vital, automatic functions of internal organs.

Sympathetic Nervous System

The division of the autonomic nervous system that arouses and expends energy; associated with the "fight or flight" response.

Parasympathetic Nervous System

The division of the autonomic nervous system that conserves energy and returns the body's functions to normal levels.

Homeostasis

A state of equilibrium or normalcy for the body.

Endocrine System

A communication system that secretes hormones, influencing various bodily functions such as food interest and aggression.

Melatonin

A hormone produced by the brain that helps regulate sleep and maintain circadian rhythms.

Adrenaline

A hormone released during stress that aids in the fight or flight response by enhancing breathing and blood circulation.

Pituitary Gland

The most influential gland of the endocrine system, regulating growth hormones, cortisol, and oxytocin.

Lesion

tissue destruction or removal

Electroencephalograph (EEG) ~ function

Electrodes measure overall brain activity

Computerized [Axial] Tomography scans (CAT/CT) ~ anatomy

Beefed up X-Ray taken different angles

Positron Emission Tomography scans (PET) ~ function

Radioactive glucose … gobbled up during brain activity

functional Magnetic Resonance Imaging (fMRI) ~ function

Detectors transmit info about areas of naturally occurring oxygen metabolism via blood in the brain

Magnetic Resonance Imaging (MRI) ~ anatomy

Magnetic fields from water molecules show 2-D soft tissue scan of brain (density and location of brain material)

brainstem

•  oldest part and central core of the brain

  • Responsible for autonomic survival functions

medulla

• base of brainstem

• controls heartbeat and breathing

Thalamus

• top of brainstem

• sensory control center

  • It receives info from all the senses (except smell), and routes the information to the appropriate higher brain regions

reticular activating system

• Inside the brainstem (right between your ears)

  • It is a neural network extending from the spinal cord right up through the thalamus - controls sleep/wake transition and arousal

cerebellum

• extends from rear of brainstem

• baseball sized

• Function include coordinating movement and balance, enabling nonverbal learning and discriminating time

• Tied to well-rehearsed movements such a dancing/athletics or playing an instrument

• Under the influences of alcohol, coordination suffers

limbic system

a neural system located below the cerebral hemispheres; it is associated with emotions and drives

What does the limbic system contain?

contains the hypothalamus (which controls the nearby pituitary gland), the amygdala, and the hippocampus

Where is the hypothalamus?

right below the thalamus

hypothalamus

It directs maintenance activities (The 5 Fs: Food/Fight/Flight/Fahrenheit/Sex), helps govern the endocrine system via the pituitary gland, and is linked to emotion and reward; runs your biological clock

amygdala

two lima-bean-sized/almond shaped neural clusters linked to the emotions, especially fear and aggression

hippocampus

• helps process memories of facts and events, before being sent to other locations in the cerebral

  • People who lose it to surgery or injury show an inability to form new memories of facts and events

cerebrum

the wrinkly stuff that we see/associate as 'brain'

corpus callosum

A group of nerve fibers that connects the two hemispheres in the cerebral cortex

What does it mean to say the brain is contralateral?

information received on one side of the body is transmitted to the opposite hemisphere of the brain

Frontal lobes

Higher processing, such as speaking, thinking, judgment, personality, and emotion

Parietal lobes

Receives sensory input for pain, warmth and cold. Functions also include perception

Occipital lobes

Visual information interpreted

Temporal lobes

Auditory/linguistic information interpreted

The Sensory and Motor cortexes

located in the very small strips, and they control the opposite side of the body

What can damage to a lobe cause?

may affect sensory ability but may not totally eliminate it

Why are brain surgeries performed with patients awake.

The brain has no sensory receptors

Association areas

areas of the cerebral cortex involved in higher cognitive functions such as learning, remembering, thinking, and speaking

• Found in all four lobes - damage to any of them rarely affects motor skills … it primarily affects cognitive skills or personality

Neuroplasticity

the brain's ability to 'rewire', especially during childhood by reorganizing after damage or by building new pathways based on experiences

• Studies show that the younger you are when the brain receives damage, the more likely it is to reorganized and make greater use of the unaffected areas

What makes it apparent that the left and right hemispheres serve different functions?

Damage

Is there a clear activity to which only one hemisphere makes a contribution?

There is no clear activity to which only one hemisphere makes a contribution.

split brain operation & side affects

• separation of corpus callosum

• cooperation between hemispheres isn't possible so the separated systems work as best they can… one usually faster than the other

Which eye corresponds with which hemisphere of brain?

• right field of each eye/left hemi

• left field of each eye/right hemi

optic chiasm

• the place where the nerves connecting the eyes to the brain cross

  • not affected by split brain operation

Which hemisphere handles language?

Language is mostly handled by the left hemisphere, regardless of whether you are right or left- handed

How many levels do perception, memory, thinking, language, and attitudes operate on?

• two levels

  • conscious, deliberate (reflective)

  • unconscious, automatic (intuitive)

Dual processing

the principle that information is often simultaneously processed on separate conscious and unconscious tracks

Blindsight

• a condition in which a person can respond to a visual stimulus without consciously experiencing it.

  • It's an extremely rare condition in which damage only to the visual cortex of the brain allows the eyes to still function and gather information from the environment…they can see without being aware that they are seeing

Heredity

 genetic transfer from parent to offspring; nature

Environment

non-genetic influences; nurture

Identical twins (monozygotic)

twins develop from a single egg that splits

Fraternal twins (dizygotic)

twins develop from separate fertilized eggs; genetically no closer than ordinary brothers/sisters…they just shared a prenatal environment

For what traits can we ask whether adopted children are morel like their biological parents (who contributed genes) or adoptive parents (who contributed a home environment)?

• For personality or any other given trait

  • Just because traits may be heritable, that doesn't necessarily mean that the traits will manifest themselves

Heritability

the extent to which variation within a group can be attributed to inherited genetic factors

• Ranges from 0 to 1; 0 indicates environment totally responsible for differences in the trait and 1 means that all variation in the trait can be accounted for genetically.

What does heritability only demonstrate?

Heritability only demonstrates the extent to which a trait is explainable by genetics, not the extent to which the trait will affect behavior in an individual outside of environmental influences

Epigenetics

the study of environmental influences on gene expression that occur without a DNA change

• Looks at what environmental factors turn genes on or off and how that info is passed to offspring

Evolutionary psychology

the study of the evolution of behavior and the mind, using principles of natural selection (traits that better help an organism survive & procreate will likely be passed to offspring)

What has given us the ability to learn and adapt to varied environments?

The gene combinations produced at conception, plus the mutations (random errors in gene replication that lead to change) that sometime result

When do neurons transmit messages?

Neurons transmit messages when stimulated by our sense or by neighboring neurons

What absorbs excess neurotransmitters?

Excess neurotransmitters are reabsorbed by the sending neuron, or drift away and are broken down by the body's enzymes

What are the 8 neurotransmitters covered in this chapter?

Acetylcholine, Dopamine, Serotonin, Norepinephrine, Endorphins, Substance P, GABA & Glutamate

Two parts of Peripheral Nervous System

• Somatic

• Autonomic

  • Sympathetic

  • Parasympathetic

How long does it take for the Endocrine system to send messages?

several seconds