Monoaminergic Neuromodulation of Sensory Processing

Abstract

All neuronal circuits are subject to neuromodulation. Modulatory effects on neuronal processing and resulting behavioral changes are most commonly reported for higher order cognitive brain functions. Comparatively little is known about how neuromodulators shape processing in sensory brain areas that provide the signals for downstream regions to operate on. In this article, we review the current knowledge about how the monoamine neuromodulators serotonin, dopamine and noradrenaline influence the representation of sensory stimuli in the mammalian sensory system. We review the functional organization of the monoaminergic brainstem neuromodulatory systems in relation to their role for sensory processing and summarize recent neurophysiological evidence showing that monoamines have diverse effects on early sensory processing, including changes in gain and in the precision of neuronal responses to sensory inputs. We also highlight the substantial evidence for complementarity between these neuromodulatory systems with different patterns of innervation across brain areas and cortical layers as well as distinct neuromodulatory actions. Studying the effects of neuromodulators at various target sites is a crucial step in the development of a mechanistic understanding of neuronal information processing in the healthy brain and in the generation and maintenance of mental diseases.

Pull-Push Neuromodulation of Cortical Plasticity Enables Rapid Bi-Directional Shifts in Ocular Dominance

“…The prevailing interpretation emerging from these studies is that neuromodulators gate cortical plasticity by enhancing sensory perception, and by promoting patterns of cortical activity suitable for plasticity induction via controlling network excitability. This is consistent with a wealth of studies documenting that neuromodulators improve perception in vivo (see Gelbard-Sagiv et al, 2018;Jacob and Nienborg, 2018;McBurney-Lin et al, 2019;Nadim and Bucher, 2014 for reviews) also affect cellular intrinsic excitability and synaptic inhibition to gate the induction of Hebbian plasticity in vitro (see Brzosko et al, 2019;Palacios-Filardo and Mellor, 2019;Pawlak et al, 2010 for reviews). We propose an additional and different mode of action: direct control of the expression, not the induction, of Hebbian plasticity via the Gq/Gs based pull-push metaplasticity mechanism that we previously demonstrated in vitro, in slices.…”

Motion perception as a model for perceptual aging

“…Due to the heterogeneity of involved processing steps, the identification of putative neuronal correlates of age-related changes is rather complex. Essentially all cortical areas are subject to substantial volume decline during aging (Raz et al, 2004), but changes in connectivity and compromised neuromodulation might be most relevant for complex perceptual decline (Damoiseaux, 2017;Jacob & Nienborg, 2018).…”

Dorsal raphe oxytocin receptors regulate the neurobehavioral consequences of social touch

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