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medium-wavelength pigment

the photopigment, present in one of the three populations of retinal cones, that has maximum sensitivity to a wavelength of 531 nm. The absence of the gene for the medium-wavelength pigment causes deuteranopia (red–green color blindness). See also long-wavelength pigment; short-wavelength pigment.

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Psychology term of the day

February 22nd 2025

excitotoxic lesion

excitotoxic lesion

a lesion caused by paroxysmal overactivity of neurons, which may be associated with seizures or occur after stroke. This is most commonly caused by overstimulation of neurons by excitatory amino acids (see excitotoxicity).