Sensory Neuromodulation

Abstract

We describe a model of neurological disease based on dysfunctional brain oscillators. This is not a new model, but it is not one that is widely appreciated by clinicians. The value of this model lies in the predictions it makes and the utility it provides in translational applications, in particular for neuromodulation devices. Specifically, we provide a perspective on devices that provide input to sensory receptors and thus stimulate endogenous sensory networks. Current forms of clinically applied neuromodulation, including devices such as (implanted) deep brain stimulators (DBS) and various, noninvasive methods such as transcranial magnetic stimulation (TMS) and transcranial current methods (tACS, tDCS), have been studied extensively. The potential strength of neuromodulation of a sensory organ is access to the same pathways that natural environmental stimuli use and, importantly, the modulatory signal will be transformed as it travels through the brain, allowing the modulation input to be consistent with regional neuronal dynamics. We present specific examples of devices that rely on sensory neuromodulation and evaluate the translational potential of these approaches. We argue that sensory neuromodulation is well suited to, ideally, repair dysfunctional brain oscillators, thus providing a broad therapeutic approach for neurological diseases.

Brain Vital Signs Detect Cognitive Improvements During Combined Physical Therapy and Neuromodulation in Rehabilitation From Severe Traumatic Brain Injury: A Case Report

“…TLNS is known to modulate sensorimotor and vestibular functions and is hypothesized to modulate multiple physiological processes via bottom-up neuromodulation of global brain function to augment neuroplasticity (Herrick and Keifer, 1998 ; Buisseret-Delmas et al, 1999 ; Marano et al, 2005 ; Wildenberg et al, 2010 , 2011 ). Current models emerging from other neuromodulation technologies, such as deep brain stimulation, have increasingly interpreted the effects as being comparable to neuromodulation through a sensory organ, with access to the same pathways and translated in similar ways as natural environmental stimuli (Black and Rogers, 2020 ). This concept is consistent with exercise-induced neuroplasticity effects cascading across the molecular, cellular, structural, functional, and behavioral levels (El-Sayes et al, 2019 ) along with demonstrated neuroprotective effects of trigeminal nerve stimulation in TBI (Chiluwal et al, 2017 ).…”

Clinical Evidence of Vestibular Dysregulation in Colicky Babies Before and After Chiropractic Treatment vs. Non-colicky Babies

“…If so, this would suggest that central neuromodulation may be accomplished not only by cutaneous vibratory stimulation to cymba of the external ear (16), but also by similar sensory stimulation of suboccipital musculature, at least in babies. Other examples of sensory neuromodulation have been reported in the literature (37).…”

“…In concordance with their central role in many regulatory processes the vestibular nuclei have extensive projections to other brainstem nuclei (37). This means that any vestibular dysregulation present may well be propagated to those very same nuclei, particularly of the autonomic system (13), which may conceivably lead to a spectrum of associated symptoms such as listed in the introduction.…”

“…Afferent proprioceptive input from upper-cervical segments (C1-3) and from axial structures project to the vestibular nuclei and indirectly to the medial cerebellar cortex and its Purkinje cells. As these Purkinje cells are inhibitory to the fastigial output nucleus, they allow the medial cerebellum to exert an inhibitory modulating influence on the vestibular system (35)(36)(37). A state of vestibular hyperactivity may ensue from even slight, subclinical, diminished inhibition by the cerebellum (13).…”

Selection of stimulus parameters for enhancing slow wave sleep events with a Neural-field theory thalamocortical computational model

“…Non-invasive methods of neural system stimulation operate at large spatial scales, and they can be by direct application of electrical or magnetic fields or by the use of sensory stimuli to modify neural activity [32, 44]. The non-invasive techniques are under active-research because of the potential clinical applications in humans.…”