Glossary

ALCOHOL NON-TOLERANT RATS (ANT rats). A rat line that has been selectively bred to be highly sensitive to motor impairment after ethanol intake.

ALLOSTERIC A term originally used to describe enzymes that have two or more receptor sites, one of which (the active site) binds the principal substrate, whereas the other(s) bind(s) effector molecules that can influence the enzyme's biological activity. More generally, it is used to describe the indirect coupling of distinct sites within a protein, mediated by conformational changes.

ALTERNATIVE SPLICING During splicing, introns are excised from RNA after transcription and the cut ends are rejoined to form a continuous message. Alternative splicing allows the production of different messages from the same DNA molecule.

COINCIDENCE DETECTION A situation in which two different subthreshold excitatory inputs are sufficiently closely timed that they summate to trigger the generation of an action potential.

GAMMA FREQUENCY NETWORK OSCILLATIONS Rhythmic neural activity with a frequency of 25–70 Hz.

GLOMERULUS Axon terminals end in various configurations within the neuropil. The most common is en passant or de passage, in which axons make simple synapses as they pass dendrites or cell bodies. By contrast, some axons end in — or produce strings of — enlargements that are often packed with synaptic vesicles. These glomerular-type endings might synapse with large numbers of dendrites. In the cerebellum, each large excitatory mossy fibre terminal contacts dendrites from many granule cells and, together with inhibitory Golgi cell axon terminals, forms a glomerular structure that is wrapped with glia.

NOOTROPIC Refers to agents that enhance memory or other cognitive functions.

PALMITOYLATION The covalent attachment of a palmitate (16-carbon, saturated fatty acid) to a cysteine residue through a thioester bond.

PARACRINE SIGNALLING A signalling process that involves the secretion from a cell of molecules that act on other cells expressing appropriate receptors in the immediate neighbourhood, rather than acting on the same cell (autocrine signalling) or on remote cells (endocrine signalling).

TETRODOTOXIN A potent marine neurotoxin that blocks voltage-gated sodium channels. Tetrodotoxin was originally isolated from the tetraodon pufferfish.

THETA FREQUENCY NETWORK OSCILLATION Rhythmic neural activity with a frequency of 4–8 Hz.