Persistent Afferent Bias: a mechanistic link between somatic disruption and autonomic dysregulation.

Persistent Afferent Bias (PAB) represents a state-dependent alteration in sensory weighting through which Somatic Disruption influences Autonomic Regulation. While the classical concept of the facilitated spinal segment provided an early neurophysiological explanation for somatic dysfunction, contemporary neuroscience increasingly favors models based on distributed neural networks and dynamic modulation of neural gain. Recent reinterpretations of facilitation as a network-level phenomenon offer a more consistent account of altered sensorimotor processing, yet remain largely confined to musculoskeletal and pain-related mechanisms and do not fully explain the origin and persistence of such bias. The present paper proposes Persistent Afferent Bias as a mechanistic link between Somatic Disruption and Autonomic Dysregulation. Within the Somato-Psychic Pathway (SPP), a theoretical model proposed by the author, PAB represents the previously unarticulated neurophysiological mechanism linking altered somatic input to changes in regulatory state. In this context, disturbances in afferent signaling-arising from Distorted Proprioceptive Information (DPI), nociceptive input, interoceptive imbalance, or other sources-lead to a reorganization of sensory weighting within neural systems. A defining feature of this process is the persistence of altered afferent conditions. Under sustained conditions, this biased processing contributes to a shift in Autonomic Regulation conceptualized as Somato-Psychic Autonomic Dysregulation (SPAD), which may subsequently give rise to broader functional manifestations, including Somato-Psychic Syndrome (SPS). This formulation situates Persistent Afferent Bias within a hierarchical regulatory cascade consistent with Directional Developmental Sequencing (DDS), in which alterations at the level of somatic input propagate to autonomic and higher-order functional domains. In this sense, PAB is not a primary phenomenon, but a secondary expression of underlying disturbances within the somatic regulatory system. Beyond its theoretical significance, this model has direct clinical implications. It supports a shift in clinical reasoning from predominantly symptomatic modulation toward identification and targeted treatment of primary somatic drivers of altered afferent input. This is particularly relevant in patients presenting with Somato-Psychic Syndrome (SPS), in whom conventional approaches focused on higher-order manifestations may fail to address the underlying regulatory disturbance. By providing a mechanistic basis for this shift, Persistent Afferent Bias enables a more etiologically grounded and hierarchically organized approach to intervention within the Somato-Psychic Pathway.