AP Psychology Chapter 3

Spinal Cord

A bundle of nerves that runs through the center of the spine and serves to transmit messages to and from the brain.

Electroencephalogram (EEG)

A device commonly used in sleep research that detects different brain waves (large scale electrical pulses from neurons in the brain).

Myelin Sheath

A fatty covering around the axon of some neurons that speeds neural impulses (acts like an insulator for a wire).

Magnetic Resonance Imaging (MRI)

A machine similar to a CAT Scan that uses magnetic fields to measure the density and location of brain material, creating a more detailed map of the brain without exposing the patient to carcinogenic radiation.

Positron Emission Tomography (PET) Scan

A machine that measures how much of a certain chemical (Ex: glucose. oxygen, etc...) is being used by the brain, thereby showing brain activity in certain locations. Different scans look for different chemicals.

Reticular Collosum

A net-like collection of neurons throughout the midbrain that controls general (non-sexual) arousal and our ability to focus. When this doesn't function properly, we fall into a deep coma.

Serotonin

A neurotransmitter associated with Mood Control. A lack of this is associated with clinical depression.

Norepinephrine

A neurotransmitter associated with alertness and general arousal (non-sexual). An excess/lack of this is associated with depression.

Functional MRI (fMRI)

A new technology that combines elements of both MRI and PET scans, it is able to show details about both brain structure and blood flow simultaneously, thereby tying brain structure and activity into one scan.

Endorphins

A set of neurotransmitters associated with pain control and that are commonly involved in addictions.

Computerized Axial Tomography (CAT) Scan

A sophisticated X-Ray machine that uses several, rotating cameras to create a detailed 3-dimensional map of a brain's structure (but not its function or activity).

Effective Psychological Environment

A term used to describe an environment in studies that compare identical twins that were raised separately. Because identical twins are so similar in looks and often in manner as well, people may treat them similarly even when they are separated from each other. This would alter the results of the study.

Motor Cortex

A thin, vertical strip at the back of the frontal lobes, this area of the brain controls all of our voluntary movement by sending signals through our nervous system to our muscles telling them to move. The right side of this area controls the left side of our body and vice versa (contralateral control), but it's also known that the top of this area controls the bottom of our body and the bottom of this area controls the top of our body.

Sensory (Somato-Sensory) Cortex

A thin, vertical strip of neurons at the front of our parietal lobes that processes incoming information from the spine about our sense of touch. The right side of this area senses the left side of our body and vice versa (contralateral control), but it's also known that the top of this area senses the bottom of our body and the bottom of this area senses the top of our body.

Peripheral Nervous System

All nerves not part of the CNS (not encased in bone). It is divided into two categories: the Somatic and the Autonomic nervous systems.

Cerebellum

Also known as the "little brain", this structure is located on the underside of the brain, towards the back. It controls habitual muscle movements and muscle memory.

Glutamate

An excitatory neurotransmitter involved in memory. An excess/lack of this is associated with migraines and seizures.

GABA (gamma-Aminobutyric Acid)

An important inhibitory neurotransmitter. An excess/lack of this can cause seizures and sleep problems.

Neuron

An individual nerve cell.

Association Area

Any area of the cerebral cortex that is not associated with receiving sensory information or controlling motor function.

Receptor Sites

Areas on a dendrite that are designed to receive neurotransmitters.

Neurotransmitters

Chemicals contained in the terminal buttons that enable neurons to communicate. Neurotransmitters fit into receptor sites on the dendrites of other neurons like a key into a lock.

Twins

Children born from the same mother who shared the womb and are (usually) born together.

Cell Body (Soma)

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

Interneurons

Neurons in the brain that take messages from the afferent neurons and either transport them across the brain, or to efferent neurons.

Efferent (Motor) Neurons

Neurons that take information from the brain to the rest of the body (exiting the brain).

Afferent (Sensory) Neurons

Neurons that take information to the brain (accessing the brain).

Excitatory Neurotransmitters

Neurotransmitters that encourage a receiving neuron to fire.

Inhibitory Neurotransmitters

Neurotransmitters that inhibit a receiving neuron's ability to fire.

Broca's Area

One of the two important areas of the brain for language skills, this area located in the Frontal Lobes is responsible for controlling the muscles used in speech. Damage to this area can cause a lack of the ability to speak.

Wernicke's Area

One of the two important areas of the brain regarding language skills, this area in the temporal lobes is responsible for interpreting and crafting language. This area interprets both the written word and verbal speech as well as uses traditional language structures to craft language that we write or speak. If this area becomes damaged, we might loose the ability to comprehend language grammar/syntax in both our own and other's speech and writing.

Lesions

Parts of the brain that have been removed (either in accidents or in surgery). This is never done for purely experimental purposes.

Split-Brain Patients

People whose Corpus Callosum has been surgically cut so that the right and left hemispheres of the Cerebral Cortex cannot interact. This is usually done as a remedy for treating severe epilepsy.

Medulla Oblongata

The section of the brain that is directly above the spinal cord (it looks like a continuation of it into the brain). It most notably controls blood pressure, heart rate, and breathing.

Pons

The small structure of the brain located just above and in front of the medulla oblongata. While known for controlling facial expressions, it is also instrumental with connecting the Midbrain with the Forebrain.

Synapse

The space between the terminal buttons of one neuron and the dendrite of another across which neurotransmitters cross to send messages between the neurons.

Genetics

The study of how our genetic information (DNA) affects our bodily processes.

Neuroanatomy

The study of the parts and functions of neurons.

Frontal Lobotomy

The surgical act of separating neurological connections between the frontal cortex and the rest of the brain.

Endocrine System

The system of glands in the body that secretes hormones to control certain biological body functions and is controlled by the hypothalamus.

Brain Lateralization (aka Hemispheric Specialization)

The unproven, experimental concept that the left hemisphere of the Cerebral Cortex is more involved in logical and patterned tasks while the right side is more involved spatial and creative tasks.

Axon

The wire-like structure of a neuron that extends from the soma and ends in the terminal buttons.

Auditory Cortices

These areas in the temporal lobes are used to process neural signals from our inner ears. Unlike other cortices involved in our physical senses, these areas are not lateralized meaning that both left and right cortices receive impulses from both our left and right ears.

Adrenal Glands

These glands are the glands that release adrenaline (epinephrine) triggering our flight-or-fight response, which therefore makes it a part of the autonomic nervous system (involuntary body functions like heartbeat).

Ovaries and Testes

These glands release the body's sex hormones (testosterone and estrogens)and have been linked to the psychological differences across the sexes.

Occipital Lobes

These lobes of the Cerebral Cortex are located at the very back of the head, farthest from the eyes. Counter intuitively, their main function is to process visual information in the visual cortex.

Parietal Lobes

These lobes of the Cerebral Cortex are located directly behind the frontal lobes, on the top back portion of our brain. They are thought to control hand-eye coordination and our sensory input. Contains the sensory cortex.

Temporal Lobes

These lobes of the Cerebral Cortex are located near our temples and ears and their main purpose is receiving and processing auditory information. These lobes contain our auditory cortices (they are separate because these lobes are split, unlike the other lobes) and the Wernicke's Area.

Midbrain

This area of the brain is located just above the hindbrain (kind of centered in the brain) and is the smallest area of the brain. This area coordinates simple movements with sensory information (Ex: Turn your head to the right while still looking at this text. This area of the brain keeps your eyes smoothly on these words).

Hippocampus

This area of the forebrain is composed of two arms that wrap around the thalamus on either side. At the end of these arms are the amygdala. Your hippocampus is responsible for processing memories. Once a memory is processed by the hippocampus, it is sent to other parts of the forebrain for storage.

Amygdala

This area of the forebrain is located at the end of each hippocampus arm and is vital to the experience of emotions.

Thalamus

This area of the forebrain is often considered the "post-office" of the brain. It receives sensory information from the spinal cord and distributes it across the forebrain to the appropriate areas.

Cerebral Cortex

This area of the forebrain, although the most famous, is probably the least understood. This area is a thin, wrinkled grey layer of densely packer neurons that covers most of the surface of the brain and is divided into two hemispheres. It is also classified into 4 different lobes.

Hypothalamus

This area of the forebrain, right next to the thalamus, controls some very important bodily functions including metabolism, body temperature, libido, hunger, thirst, and the endocrine system (hormones).

Forebrain

This largest area of the brain is what arguably makes humans human. This area is largely out of proportion to most other animals and houses thought, reasoning, logic, and problem solving skills. Specific sections of this area include the thalamus, hypothalamus, amygdala, cerebral cortex, and hippocampus.

Monozygotic (Identical) Twins

Twins who are both from the same initial zygote that split into two different zygotes in early development, thereby giving each twin the same exact genes. This is very useful for psychologists when attempting to measure the effects of nature-vs-nurture in certain situations.

New Brain

Forebrain

Old Brain

Hindbrain and Midbrain combined

Reflexes

Reactions to certain stimuli that are not processed by the brain, but instead by the spinal cord, normally because getting the information to the brain and back would take too long. Ex: touching a hot object and jerking your hand back.

Dendrites

Root-like parts of a neuron that stretch out from the cell body and form synaptic connections with other cells.

Threshold

The amount of neurotransmitters that need to be received by a receptor site to cause that neuron to fire.

Visual Cortex

The area in the Occipital Lobes that receives and processes information from our eyes. Impulses from the right half of each retina are processed in the right half of this area, and vice versa with the left sides.

Corpus Callosum

The area of the forebrain that connects the two hemispheres of the Cerebral Cortex.

Prefrontal Cortex

The area on the Frontal Lobes that is located farthest forwards (directly behind the eyes). It is thought to be the brain's central executive and has great influence on thought processes, foreseeing consequences, and setting goals as well as developing abstract thoughts and emotional control.

Hindbrain

The brain structures located in the top part of the spinal cord. These control our basic life functions and contain the medulla, pons, and cerebellum.

Terminal Buttons (A.K.A. End Buttons, Terminal Branches of the Axon, or Synaptic Knobs)

The branched end of an axon that contains neurotransmitters and helps to form the synaptic connection.

Action Potential

The change in the charge of a neuron when it fires that travels from the dendrites to the axon in a wave at approximately 120 meters per second. Before a neuron fires, its

Brain Plasticity

The concept that certain parts of the brain could create connections that would alter its purpose and ability or add another purpose, thereby showing that sometimes certain functions aren't always processed by one area of the brain. This may occur in the event of damage to the brain.

Nature vs. Nurture Concept

The concept that our psychological uniqueness and variability stems from a combination of biological factors such as genetics and hormones (nature) as well as environmental factors such as parenting styles and culture (nurture).

Neural Firing

The electrochemical process in which electricity travels from the dendrites of a neuron to its terminal buttons (electro) who thereby release neurotransmitters into the neighboring neurons (chemical).

All-Or-None Principle

The idea that a neuron either fires completely or not at all with no in between.

Frontal Lobes

The largest lobes of the Cerebral Cortex. These lobes are positioned directly behind the eyes and extend all the way back to the ears. These lobes include the prefrontal cortex, Broca's area, and the motor cortex.

Sympathetic Nervous System

The nerves in our body that elevate our response to stress (fight-or-flight). They will slow certain processes, like digestion, but speed others, like heartbeat and respiration.

Parasympathetic Nervous System

The nerves in our body that reduce our response to stress (fight-or-flight). Returns our bodies back to normal once stress has been alleviated.

Autonomic Nervous System

The nerves that control our automatic biological processes: breathing, heartbeat, organs, endocrine system, etc..., as well as the fight-or-flight response. Is divided into two categories: the Sympathetic and Parasympathetic nervous systems.

Somatic Nervous System

The nerves that control our voluntary muscle movements. The motor cortex of the brain sends information to the somatic nervous system which tells our muscles to move.

Dopamine

The neurotransmitter associated with motor movement and alertness. A lack of this is associated with Parkinson's disease. An excess is associated with schizophrenia.

Acetylcholine

The neurotransmitter associated with motor movement. A lack of this is associated with Alzheimer's disease.

Contralateral Control

The principle that each hemisphere of our cerebral cortex controls the motor function of, and receives sensory information from, the opposite side of the body (left hemisphere to right side, right hemisphere to left side).

Central Nervous System (CNS)

Your brain and spinal cord (all nerves housed in bone).