Optokinetic nystagmus (OKN), the reflexive eye movements evoked by a moving field, has recently gained interest among researchers as a useful tool to assess conscious perception. When conscious perception and stimulus are dissociated, such as in binocular rivalry-when dissimilar images are simultaneously presented to each eye and perception alternates between the two images over time-OKN correlates with perception rather than with the physical direction of the moving field. While this relationship is well established in healthy subjects, it is yet unclear whether it also generalizes to clinical populations, for example, patients with Parkinson's disease.
View Article and Find Full Text PDFAmbient light affects multiple physiological functions and behaviors, such as circadian rhythms, sleep-wake activities, and development, from flies to mammals. Mammals exhibit a higher body temperature when exposed to acute light compared to when they are exposed to the dark, but the underlying mechanisms are largely unknown. The body temperature of small ectotherms, such as Drosophila, relies on the temperature of their surrounding environment, and these animals exhibit a robust temperature preference behavior.
View Article and Find Full Text PDFDiscriminating a direction of frequency change is an important ability of the human auditory system, although temporal dynamics of neural activity underlying this discrimination remains unclear. In the present study, we recorded auditory-evoked potentials when human subjects explicitly judged a direction of a relative frequency change between two successive tones. A comparison of two types of trials with ascending and descending tone pairs revealed that neural activity discriminating a direction of frequency changes appeared as early as the P1 component of auditory-evoked potentials (latency 50 ms).
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