title: [Sound improves distinction of low intensities of light in the visual cortex of a rabbit].
abstract: Electrodes were implanted into cranium above the primary visual cortex of four rabbits (Orictolagus cuniculus). At the first stage, visual evoked potentials (VEPs) were recorded in response to substitution of threshold visual stimuli (0.28 and 0.31 cd/m2). Then the sound (2000 Hz, 84 dB, duration 40 ms) was added simultaneously to every visual stimulus. Single sounds (without visual stimuli) did not produce a VEP-response. It was found that the amplitude ofVEP component N1 (85-110 ms) in response to complex stimuli (visual and sound) increased 1.6 times as compared to "simple" visual stimulation. At the second stage, paired substitutions of 8 different visual stimuli (range 0.38-20.2 cd/m2) by each other were performed. Sensory spaces of intensity were reconstructed on the basis of factor analysis. Sensory spaces of complexes were reconstructed in a similar way for simultaneous visual and sound stimulation. Comparison of vectors representing the stimuli in the spaces showed that the addition of a sound led to a 1.4-fold expansion of the space occupied by smaller intensities (0.28; 1.02; 3.05; 6.35 cd/m2). Also, the addition of the sound led to an arrangement of intensities in an ascending order. At the same time, the sound 1.33-times narrowed the space of larger intensities (8.48; 13.7; 16.8; 20.2 cd/m2). It is suggested that the addition of a sound improves a distinction of smaller intensities and impairs a dis- tinction of larger intensities. Sensory spaces revealed by complex stimuli were two-dimensional. This fact can be a consequence of integration of sound and light in a unified complex at simultaneous stimulation.
authors.forename: V B
authors.initials: VB
authors.lastname: Polianskiĭ
authors.forename: D E
authors.initials: DE
authors.lastname: Alymkulov
authors.forename: D V
authors.initials: DV
authors.lastname: Evtikhin
authors.forename: B V
authors.initials: BV
authors.lastname: Chernyshev
mesh_terms: D000818:Animals; D001307:Auditory Perception; D005074:Evoked Potentials, Visual; D008027:Light; D010775:Photic Stimulation; D011817:Rabbits; D013016:Sound; D014793:Visual Cortex