Producción CyT
Book of abstracts of the Bernstein Conference 2020 - Cross frequency couplings and directionality between neuronal oscillations in the somatosensory pathway of macaque monkeys during a vibrotactile discrimination task
Congreso
Autoría:
Zizumbo Colunga J ; Parra S ; Urdapilleta E ; Dellavale DFecha:
2020Editorial y Lugar de Edición:
Bernstein Coordination Site (BCOS) Branch Office of the Forschungszentrum Jülich at the University of FreiburgResumen *
The usual approach to the somatosensory pathway considers S1 (primary somatosensory cortex) as the entry of information to cortex, which is then passed to S2 (secondary somatosensory cortex); from there information is broadcast to frontal cortices. Within these, myriad signals appear and are maintained in working memory: highly processed representations of stimuli, task rules, movement preparation and behavioural feedback.However, there are many questions regarding the origins of these signals. One question is whether a signal is locally computed in an area or comes from a different one. In the second case, discerning between feedforward and feedback propagation is another important question. We contribute to these issues by studying the local field potential (LFP) rhythms and their interactions between areas in the somatosensory pathway. The results inform previous findings from single neuron spike coding and point to new possible studies.Since previous studies found S2 to have both faithful representations of stimuli and more abstract signals, S2 is excellent to study these questions. Thus, S2 was used as a “pivot”, exploring its interactions with two other areas: S1, an upstream sensory area where feedforward interactions are expected to dominate; and medial premotor cortex (MPC), an instance of a frontal, downstream area where interactions in both directions come into play. Importantly, the rhythms within each area were also characterized to complete the picture of area interactions versus local dynamics.The LFP data was registered while rhesus monkeys performed a vibrotactile discrimination task, which involved the sequential presentation of two stimuli and a delayed decision report. The features of the LFP dynamics were computed using the Filter-Hilbert method; these features include the temporal evolution of power, phase and frequency. Their (nonlinear) interactions within and across frequency bands (e.g. intra- and inter-area coherence and cross-frequency couplings) were also studied.The inter-area directionality and cross frequency coupling was analyzed by quantifying the group delay and bi-coherence (e.g. bi-Phase Locking Value). Intra- and cross-frequency couplings were computed using non parametric methods (e.g. Time Locked Index). In addition, synthetic control methods for causal inference based on Bayesian structural time series models were used to estimate contrafactual features of the neural dynamics of the relevant task periods. Información suministrada por el agente en SIGEVAPalabras Clave
Somatosensory pathwayCross frequency couplingsVibrotactile discrimination taskMacaque monkeys