Monkey Area MT Latencies to Speed Changes Depend on Attention and Correlate with Behavioral Reaction Times

• Published in: Neuron (Cambridge, Mass.) Mass.), 2013-05, Vol.78 (4), p.740-750
• Main Authors: Galashan, F. Orlando, Saßen, Hanna C., Kreiter, Andreas K., Wegener, Detlef
• Format: Article
• Language: English
• Subjects: Animals; Attention - physiology; Behavior; Behavior, Animal - physiology; Confidence intervals; Evoked Potentials - physiology; Field Dependence-Independence; Macaca mulatta; Psychomotor Performance - physiology; Reaction Time - physiology; Studies; Visual Cortex - physiology
• ISSN: 0896-6273; 1097-4199
• DOI: 10.1016/j.neuron.2013.03.014

Selective visual attention is known to be associated with characteristic modulations of neuronal activity in early visual cortex, but there is only rare evidence showing that these neuronal modulations are directly related to attention-dependent behavioral improvements. Here, we describe a strong, transient increase in the response of neurons in the mediotemporal (MT) area to behaviorally relevant speed changes that is not only modulated by attention but also highly correlated with the animal’s performance. In trials with fast reaction time (RT), this transient component occurs with short latency, whereas latency increases monotonically with slower RT. Importantly, RTs are related not to the firing rate modulation during sustained attentive tracking of the target prior to the speed change but to the variability of the neuronal response. Our findings suggest a direct link between attention-dependent response modulations in early visual cortex and improved behavioral performance. •Attention modulates neuronal response latency to a behaviorally relevant speed change•Behavioral reaction times correlate with neuronal response latencies•Firing rates prior to the speed change have no relation to reaction times•Fast and slow reaction times are preceded by small and large Fano factors How does attention-dependent modulation of neuronal activity relate to behavioral improvements? Galashan et al. find that attention reduces neuronal response latency already in early visual cortex and show a close relationship between these latency reductions and behavioral reaction times.