title: Early malnutrition diffusely affects children contrast sensitivity to sine-wave gratings of different spatial frequencies.
abstract: Cognitive, behavioral and neurophysiological deficits, associated with malnutrition, are described in the literature. The aim of this study was to evaluate the visual contrast sensitivity in children with early malnutrition, classified according to the anthropometric parameters of Waterlow. Visual contrast sensitivity of 16 boys from 7-10 years old was measured using the staircase psychophysical method, using vertical sine-wave gratings of 0.25, 1.0, 2.0 and 8.0 cycles per degree (cpd) of visual angle. Malnourished children were approximately 3.3, 10.9 and 6.6 times less sensitive to the frequencies of 0.25, 1.0 and 2.0 cpd, respectively, although they were approximately 1.1 times more sensitive to the frequency of 8.0 cpd. It is likely that early malnutrition adversely affected the magnocellular pathway on the one hand, since early malnourished children needed more contrast to detect low and low-to-medium frequencies; on the other hand, early malnutrition did not affect the parvocellular pathway, since there was an increase of sensitivity to the highest frequency.
authors.affiliation: Laboratório de Percepção, Neurociências e Comportamento (LPNeC), Federal University of Paraiba Psychology Department, Paraiba, Brasil. natanael_labv@yahoo.com.br
authors.forename: Natanael Antonio
authors.initials: NA
authors.lastname: Dos Santos
authors.forename: Caroline Costa Gomes
authors.initials: CC
authors.lastname: Alencar
mesh_terms: D001921:Brain / Q000254:growth & development; D002648:Child; D015350:Contrast Sensitivity / Q000502:physiology*; D006801:Humans; D008297:Male; D044342:Malnutrition / Q000503:physiopathology*; D014785:Vision, Ocular / Q000502:physiology