Modules 11-15

Lesion

Tissue destruction

A naturally or experimentally caused destruction of brain tissue

Electroencephalogram (EEG)

An amplified recording of the waves of electrical activity sweeping across the brain’s surface; measured by electrodes placed on the scalp

Helps identify seizures and abnormalities in brain activity

CT (computed tomography) Scan

(aka CAT scan)

A series of X-ray photographs that examine brain structure and yields information about the exact shape and structure, which creates 3D images out of slices of the brain

Can help diagnose tumors

PET (positron emission tomography) Scan

A visual display of brain activity that detects where a radioactive form of glucose goes while the brain performs a given task

Examines brain function by observing the amount of metabolic activity in different brain regions

MRI (magnetic resonance imaging)

A technique that assembles a picture of the brain using strong magnetic pulses

Can show healthy tissue, tissue degeneration, tumors, and blood clots or leaks that may signal strokes

fMRI (functional MRI)

A technique for revealing bloodflow and oxygen use and, therefore, brain activity by comparing successive MRI scans

Shows brain function as well as its structure

Brainstem

The oldest part and central core of the brain, beginning where the spinal cord swells as it enters the skull

Responsible for automatic survival functions

Medulla

The base of the brainstem

Controls heartbeat and breathing

Thalamus

The brain’s sensory control center, located on top of the brainstem

It directs messages to the sensory receiving areas in the cortex and transmits replies to the cerebellum and medulla

Reticular Formation

A nerve network that travels through the brainstem and thalamus and plays an important role in controlling arousal

Pons

Regulates waking and relaxing and facial expressions

Located at the base of the brain, links medulla to the thalamus

Cerebellum

The “little brain” at the rear of the brainstem

Functions include processing sensory input, coordinating movement output and balance, and enabling nonverbal learning and memory

Limbic System

Neural system (including the hippocampus, amygdala, hypothalamus, and pituitary gland) located below the cerebral hemispheres

Associated with emotions and drives

Hippocampus

Helps process explicit messages for storage

Responsible for the formation of new memories

Amygdala

Two lima bean sized neural clusters in the limbic system

Linked to emotion

Hypothalamus

A neural structure lying below the thalamus

It directs several maintenance activities (eating, drinking, body temperature), helps govern the endocrine system via the pituitary gland, and is linked to emotion and reward

Cerebral Cortex

The intricate fabric of interconnected neural cells covering the cerebral hemispheres

The body’s ultimate control and information processing center

Glial Cells (glia)

Cells in the nervous system that support, nourish, and protect neurons

They may also play a role in learning and thinking

Frontal Lobes

Portion of the cerebral cortex lying just behind the forehead

Involved in speaking, muscle movements, and in making plans and judgements

Parietal Lobes

Portion of the cerebral cortex lying at the top of the head and toward the rear

Receives sensory input for touch and body position

Occipital Lobes

Portion of the cerebral cortex lying at the back of the head

Includes areas that receive information from the visual fields

Temporal Lobes

Portion of the cerebral cortex lying roughly above the ears

Includes the auditory areas, each receiving information primarily from the opposite ear

Broca’s Area

Located in the frontal lobes in the left hemisphere

Helps choose words and produce language

If malfunctioned, speech makes sense but isn’t fluent and is broken

Wernicke’s Area

Located in the temporal lobe in the left hemisphere

Helps understand speech

If malfunctioned, able to produce words but the word order will not make sense

Motor Cortex

An area at the rear of the frontal lobes that controls voluntary movements

Somatosensory Cortex

Area at the front of the parietal lobes that registers and processes body touch and movement sensations

Association Areas

Areas of the cerebral cortex that are not involved in primary motor or sensory functions

Rather, they are involved in higher mental functions such as learning, remembering, thinking and speaking

Plasticity

The brain’s ability to change, especially during childhood, by reorganizing after damage or by building new pathways based on experience

Neurogenesis

The formation of new neurons

Corpus Callosum

The large band of neural fibers connecting the two brain hemispheres and carrying messages between them

Split Brain

A condition resulting from surgery that isolates the brain’s two hemispheres by cutting the fibers (mainly those of the corpus callosum) connecting them

Consciousness

Our awareness of ourselves and our environment

Cognitive Neuroscience

The interdisciplinary study of the brain activity linked with cognition (including perception, thinking, memory, and language)

Dual Processing

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

Behavior Genetics

The study of the relative power and limits of genetic and environmental influences on behavior

Environment

Every external influence, from prenatal nutrition to the people and things around us

Chromosomes

Threadlike structures made of DNA molecules that contain the genes

DNA

A complex molecule containing the genetic information that makes up the chromosomes

Genes

The biochemical units of heredity that make up the chromosomes

Segments of DNA capable of synthesizing proteins

Genome

The complete instructions for making an organism, consisting of all the genetic material in that organism’s chromosomes

Identical Twins (monozygotic twins)

Twins who develop from a single fertilized egg that splits in two, creating two genetically identical organisms

Fraternal Twins (dizygotic twins)

Twins who develop from separate fertilized eggs

They are genetically no closer than brothers and sisters, but they share a fetal environment

Molecular Genetics

The subfield of biology that studies the molecular structure and function of genes

Heritability

The proportion of variation among individuals that we can attribute to genes

May vary, depending on the range of populations and environments studied

Interaction

The interplay that occurs when the effect of one factor (such as environment) depends on another factor (such as heredity)

Epigenetics

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

Evolutionary Psychology

The study of the evolution of behavior and the mind, using principles of natural selection

Natural Selection

The principle that, among the range of inherited trait variations, those contributing to reproduction and survival will most likely be passed on to succeeding generations

Mutation

A random error in gene replication that leads to a change