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How the brain selects goals for movements remains unknown. The system designed to move the eyes rapidly, the saccadic system, may play a role. Here we ask how sensory signals within a saccade area are influenced by selecting and preparing a saccade. Trained monkeys made or withheld saccades, based on a color cue, to targets varying in luminance contrast. We(More)
A feature of neurons in the mammalian superior colliclus (SC) is the robust discharge of action potentials preceding the onset of rapid eye movements called saccades. The burst, which commands ocular motoneurons, is often preceded by persistent, low-level activity, likely reflecting neuronal processes such as target selection, saccade selection and(More)
In addition to its role in saccade generation, the superior colliculus (SC) is involved in target selection, saccade selection, and shifting the focus of spatial attention. Here, we investigated the influence of saccade selection on sensory interactions within single response fields (RFs) of SC neurons. One or two differently shaped stimuli were presented(More)
Astronomers and physicists noticed centuries ago that visual spatial resolution is higher for dark than light stimuli, but the neuronal mechanisms for this perceptual asymmetry remain unknown. Here we demonstrate that the asymmetry is caused by a neuronal nonlinearity in the early visual pathway. We show that neurons driven by darks (OFF neurons) increase(More)
By performing a whole genome screen in an F2 intercross of two strains of mice (A/J and C57BL/6J), which differ markedly in their behavioral response to a brightly lit open field (O-F), we have mapped several quantitative trait loci (QTL) for this complex behavioral phenotype. QTL on chromosomes 1 and 10 were identified that affect both initial ambulation(More)
To define the genetic contributions affecting individual differences in seizure threshold, a beta carboline [methyl-beta-carboline-3-carboxylate (beta-CCM)]-induced model of generalized seizures was genetically dissected in mice. beta-CCM is a GABAA receptor inverse agonist and convulsant. By measuring the latency to generalized seizures after beta-CCM(More)
Recordings from local field potentials (LFPs) are becoming increasingly common in research and clinical applications, but we still have a poor understanding of how LFP stimulus selectivity originates from the combined activity of single neurons. Here, we systematically compared the stimulus selectivity of LFP and neighboring single-unit activity (SUA)(More)
Visual information is mediated by two major thalamic pathways that signal light decrements (OFF) and increments (ON) in visual scenes, the OFF pathway being faster than the ON. Here, we demonstrate that this OFF temporal advantage is transferred to visual cortex and has a correlate in human perception. OFF-dominated cortical neurons in cats responded ∼3 ms(More)
Vision emerges from activation of chromatic and achromatic retinal channels whose interaction in visual cortex is still poorly understood. To investigate this interaction, we recorded neuronal activity from retinal ganglion cells and V1 cortical cells in macaques and measured their visual responses to grating stimuli that had either luminance contrast(More)
Local field potentials (LFPs) have become an important measure of neuronal population activity in the brain and could provide robust signals to guide the implant of visual cortical prosthesis in the future. However, it remains unclear whether LFPs can detect weak cortical responses (e.g., cortical responses to equiluminant color) and whether they have(More)