title: Theta coupling between V4 and prefrontal cortex predicts visual short-term memory performance.
abstract: Short-term memory requires communication between multiple brain regions that collectively mediate the encoding and maintenance of sensory information. It has been suggested that oscillatory synchronization underlies intercortical communication. Yet, whether and how distant cortical areas cooperate during visual memory remains elusive. We examined neural interactions between visual area V4 and the lateral prefrontal cortex using simultaneous local field potential (LFP) recordings and single-unit activity (SUA) in monkeys performing a visual short-term memory task. During the memory period, we observed enhanced between-area phase synchronization in theta frequencies (3-9 Hz) of LFPs together with elevated phase locking of SUA to theta oscillations across regions. In addition, we found that the strength of intercortical locking was predictive of the animals' behavioral performance. This suggests that theta-band synchronization coordinates action potential communication between V4 and prefrontal cortex that may contribute to the maintenance of visual short-term memories.
authors.affiliation: Max Planck Institute for Biological Cybernetics, Department of Physiology of Cognitive Processes, Tuebingen, Germany. s.liebe@ucl.ac.uk
authors.forename: Stefanie
authors.initials: S
authors.lastname: Liebe
authors.forename: Gregor M
authors.initials: GM
authors.lastname: Hoerzer
authors.forename: Nikos K
authors.initials: NK
authors.lastname: Logothetis
authors.forename: Gregor
authors.initials: G
authors.lastname: Rainer
mesh_terms: D000200:Action Potentials; D000818:Animals; D001931:Brain Mapping; D004569:Electroencephalography; D005074:Evoked Potentials, Visual / Q000502:physiology; D008253:Macaca mulatta; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D009474:Neurons / Q000502:physiology; D009483:Neuropsychological Tests; D010775:Photic Stimulation / Q000379:methods; D017397:Prefrontal Cortex / Q000166:cytology / Q000502:physiology*; D011930:Reaction Time; D013826:Theta Rhythm / Q000502:physiology*; D013997:Time Factors; D014793:Visual Cortex / Q000166:cytology / Q000502:physiology*; D014795:Visual Pathways / Q000502:physiology*