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