Macaque V1 Neuron Activity Links Internal States to Reaction Time, Perceptual Choice

The brain's capacity to process visual information is essential for everything from simple reaction times to complex decisions in demanding environments like sports or driving [1, 2, 3]. While perception is clearly driven by external sensory input, it is also profoundly shaped by an individual's internal state, such as alertness or expectation [4, 5]. However, the precise neural mechanisms by which these internal states modulate the earliest stages of sensory processing to influence behavior have remained largely undefined. A recent study in macaques provides new evidence on how these internal and external worlds interact within the primary visual cortex.