Exam 4 Review:  Chapter 12:  Electrical and Chemical Activity in the Brain

electroencephalogram (EEG) - A diagnostic test which records a graphic record of the electrical activity of the brain (brain waves) using highly sensitive electrodes attached to the scalp and connected to an electroencephalograph; commonly used in the evaluation of neurological diseases, e.g., seizures, epilepsy, etc.; aka encephalogram.

brain waves - Brain waves, or the "EEG", are electrical signals that can be recorded from the brain, either directly or through the scalp; the kind of brain wave recorded depends on the behavior of the subject, and is the visible evidence of the kind of neuronal (brain cell) processing necessary for that behavior; the most common coherent patterns are classified as alpha (subject relaxed), beta (subject concentrating, alert, anxious, panicky), delta (sleep or disconnection from body), and theta (creative, pleasurable or confused states).

brain lateralization - A significant division of labor recognized in the cerebrum in which (1) somatic sensory information from and somatic motor commands to the left side of the body are routed from/to the right cerebral hemisphere and vice versa; (2) the left side of the brain is dominant for language skills in 95% of right-handed individuals and in 60-70% of left-handed individuals; (3) for a majority of individuals the left cerebral hemisphere is also dominant for math skills and logic; (4) for a majority of individuals the right cerebral hemisphere is dominant for spatial abilities, face recognition, visual imagery, and musical skills.
 
neurosecretory cells - A diverse group of specialized cells derived from nervous tissue which produce regulatory hormones which are secreted into the blood stream to circulate and reach their target organs to trigger a response; within the central nervous system, neurosecretory cells are found primarily in the hypothalamus where the secretions are transferred to the pituitary gland and in the pineal body; within the peripheral nervous system, neurosecretory cells are found in the adrenal medulla and within the walls of the gastrointestinal tract.

neuromodulators - Molecules which potentiate or inhibit the transmission of a nerve impulse but are not the actual means of transmission itself; while they are similar to neurotransmitters, they do not directly trigger impulse transmission, but facilitate or suppress the initiation of impulse transmission; another difference is that neuromodulators may simultaneously affect larger regions within the CNS than simply an individual synapse.

acetylcholine (ACh) - A CNS & PNS neurotransmitter which is a derivative of choline; it is synthesized, stored and released at the ends of nerve fibers at the neuromuscular junction. in the somatic and parasympathetic nervous systems, and in the brain where it may also act as a neuromodulator.

biogenic amines - a wide variety of small compounds derived by simple enzymatic modification of various individual amino acids which have active physiological properties such as serving as hormones, local hormones, neurotransmitters, neuromodulators, etc.

neuropeptides - Any of various short-chain peptides (oligopeptides) found in brain tissue, such as endorphins; many neuropeptides are also synthesized and released as hormones by non-neuronal cells; these neuroactive molecules coordinate, integrate, and regulate physiological processes in all organisms, throughout all phases of development; acting as neurohormones, neurotransmitters, and/or neuromodulators, they maintain physiological homeostasis and influence important behavioral patterns.

enkephalins - Either of two closely related CNS neuropeptides (pentapeptides) having opiate qualities (producing pain relief by central inhibition of incoming pain impulses) and occurring in the brain, spinal cord, and other parts of the body.

endorphins - Any of a group of large peptide neurohormones that bind to opiate receptors and are found mainly in the brain; they reduce the sensation of pain and affect emotions.

dynorphins - A class of opioid peptides which have modulatory effects on several CNS functions, including memory acquisition, stress and movement.

gas neurotransmitters - A recently discovered group of novel neurotransmitters which are small soluble molecules synthesized on demand (when the action potential arrives) by certain neurons; these compounds then diffuse into nearby neurons or even back into the sending neuron to stimulate a variety of effects; e.g., nitric oxide (NO) and carbon monoxide (CO).
 

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