lesion
tissue destruction. A brain lesion is a naturally or experimentally caused destruction of brain tissue
electroencephalogram
an amplified recording of the waves of electrical activity that sweep across the brain's surface. These waves are measured by electrodes placed on the scalp.
CT (computed tomography) scan
A series of x-ray photographs taken from different angles and combined by computer into a composite representation of a slice through the body (CAT Scan)
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
MRI (magnetic resonance imaging)
a technique that uses magnetic fields and radio waves to produce computer-generated images that distinguish among different types of soft tissue; allows us to see structures within the brain
fMRI (functional MRI)
a technique for revealing bloodflow and, therefore, brain activity by comparing successive MRI scans. fMRI scans show brain function.
brainstem
The oldest part and central core of the brain, beginning where the spinal cord swells as it enters the skull; the brainstem is responsible for automatic survival functions
medulla
the base of the brainstem; controls heartbeat and breathing
reticular formation
a nerve network in the brainstem that plays an important role in controlling arousal.
thalamus
the brain's sensory switchboard, 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
cerebellum
the "little brain" attached to the rear of the brainstem; its functions include processing sensory input and coordinating movement output and balance
limbic system
a doughnut-shaped system of neural structures at the border of the brainstem and cerebral hemispheres; associated with emotions such as fear and aggression and drives such as those for food and sex. Includes the hippocampus, amygdala, and hypothalamus.
amygdala
two lima bean-sized neural clusters that are components of the limbic system and are linked to emotion
hypothalamus
a neural structure lying below (hypo) 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
the intricate fabric of interconnected neural cells that covers the cerebral hemispheres; the body's ultimate control and information-processing center
glial cells
cells in the nervous system that support, nourish, and protect neurons
frontal lobes
the portion of the cerebral cortex lying just behind the forehead; involved in speaking and muscle movements and in making plans and judgments
parietal lobes
the 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
the portion of the cerebral cortex lying at the back of the head; includes the visual areas, which receive visual information from the opposite visual field
temporal lobes
the portion of the cerebral cortex lying roughly above the ears; includes the auditory areas, each of which receives auditory information primarily from the opposite ear
motor cortex
an area at the rear of the frontal lobes that controls voluntary movements
sensory cortex
the 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
aphasia
impairment of language, usually caused by left hemisphere damage either to Broca's area (impairing speaking) or to wernicke's area (impairing understanding)
Broca's area
controls language expression-an aread of the frontal, usually in the left hemisphere, that directs the muscle movements involved in speech
Wernicke's area
controls language reception-a brain area involved in language comprehension and expression;usually in the left temporal lobe
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