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grandmother cell

any hypothetical neuron in the visual association cortex that is stimulated only by a single highly complex and meaningful stimulus, such as a particular individual (e.g., one’s grandmother) or a particular well-known object (e.g., the Sydney Opera House). It is an extension of the feature detector concept to a degree that has been dismissed by many as overly simplistic and untenable. However, research on the activity patterns of single neurons in memory-linked areas of the brain has provided support for the concept by revealing a much higher degree of neuronal specificity than previously believed. [coined in 1969 by U.S. cognitive scientist Jerome Ysroael Lettvin (1920–2011), although the concept itself was proposed two years earlier by Polish neurophysiologist Jerzy Konorski (1903–1973), who referred to it as a gnostic neuron]

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Psychology term of the day

May 26th 2024

GABAA receptor

GABAA receptor

one of the two main types of receptor protein that bind the neurotransmitter gamma-aminobutyric acid (GABA), the other being the GABAB receptorgabab-receptor. It is located at most synapses of most neurons that use GABA as a neurotransmitter. The predominant inhibitory receptor in the central nervous system, it functions as a chloride channel (see ion channel). GABA agonists, such as the barbiturates and benzodiazepines, enhance the binding of GABA to GABAA receptors, allowing for increased conductance of chloride through the ion channel and thereby hyperpolarizing the neuron and inhibiting its activity. GABA antagonists, such as bicuculline and picrotoxin, block the inhibitory effects of GABA at this receptor. Many other substances, including alcohol (ethanol), are thought to exert at least part of their effect via interaction at the GABAA receptor.