Neural correlations during a cognitive task are central to study brain information processing and computation. However, they have been poorly analyzed due to the difficulty of recording simultaneous single neurons during task performance. In the present work, we quantified neural directional correlations using spike trains that were simultaneously recorded in sensory, premotor, and motor cortical areas of two monkeys during a somatosensory discrimination task. Upon modeling spike trains as binary time series, we used a nonparametric Bayesian method to estimate pairwise directional correlations between many pairs of neurons throughout different stages of the task, namely, perception, working memory, decision making, and motor report. We find that solving the task involves feedforward and feedback correlation paths linking sensory and motor areas during certain task intervals. Specifically, information is communicated by task-driven neural correlations that are significantly delayed across secondary somatosensory cortex, premotor, and motor areas when decision making takes place. Crucially, when sensory comparison is no longer requested for task performance, a major proportion of directional correlations consistently vanish across all cortical areas.

R.R.’s research was partially supported by International Research Scholars Award 55005959 from the Howard Hughes Medical Institute, Dirección de Personal Académico de la Universidad Nacional Autónoma de México Grant IN203210, and Consejo Nacional de Ciencia y Tecnología Grant CB-2009-01-130863. V.N. was supported by a Ministerio de Educación y Ciencia-Fullbright Postdoctoral Fellowship from the Spanish Ministry of Science and Technology and Dirección de Personal Académico de la Universidad Nacional Autónoma de México. Support for this work was provided by European Project FP7-ICT BrainScales (G.D. and M.M.-G). In addition, G.D. was supported by the European Research Council Advanced Grant DYSTRUCTURE (Grant 295129) and by the Spanish Research Project SAF2010-16085. A.T.C. was supported by the European Community’s Seventh Framework Programme (FP7/2007-2013) under Grant Agreement PEOPLE-2012-IEF-329837.