Nonmonotonic spatial structure of interneuronal correlations in prefrontal microcircuits

• Published in: Proceedings of the National Academy of Sciences - PNAS Vol. 115; no. 15; pp. E3539 - E3548
• Main Authors: Safavi, Shervin, Dwarakanath, Abhilash, Kapoor, Vishal, Werner, Joachim, Hatsopoulos, Nicholas G., Logothetis, Nikos K., Panagiotaropoulos, Theofanis I.
• Format: Journal Article
• Language: English
• Published: United States National Academy of Sciences 10.04.2018
• Series: PNAS Plus
• Subjects: Action Potentials - physiology; Anesthesia; Animals; Biological Sciences; Connectome - methods; Convexity; Correlation; Correlation analysis; Decay; Interneurons; Macaca; Male; Nerve Net - physiology; Neural networks; Neural Pathways - physiology; Neurons; Neurons - physiology; Photic Stimulation; PNAS Plus; Prefrontal cortex; Prefrontal Cortex - anatomy & histology; Prefrontal Cortex - physiology; Probability; Scanning electron microscopy; Sleep and wakefulness; Somatosensory cortex; Spatial Analysis; Structure-Activity Relationship; Variation; Visual cortex; Visual Cortex - anatomy & histology; Visual Cortex - physiology; Visual stimuli; Wakefulness; functional connectivity; network structure; prefrontal cortex; long-range interactions; noise correlations
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.1802356115

Correlated fluctuations of single neuron discharges, on a mesoscopic scale, decrease as a function of lateral distance in early sensory cortices, reflecting a rapid spatial decay of lateral connection probability and excitation. However, spatial periodicities in horizontal connectivity and associational input as well as an enhanced probability of lateral excitatory connections in the association cortex could theoretically result in nonmonotonic correlation structures. Here, we show such a spatially nonmonotonic correlation structure, characterized by significantly positive long-range correlations, in the inferior convexity of the macaque prefrontal cortex. This functional connectivity kernel was more pronounced during wakefulness than anesthesia and could be largely attributed to the spatial pattern of correlated variability between functionally similar neurons during structured visual stimulation. These results suggest that the spatial decay of lateral functional connectivity is not a common organizational principle of neocortical microcircuits. A nonmonotonic correlation structure could reflect a critical topological feature of prefrontal microcircuits, facilitating their role in integrative processes.