Present and Accounted For: Sensory Stimulation and Parietal Neuroplasticity

Abstract

There are commonalities between neurologic syndromes arising from lesions of the parietal cortex and psychiatric syndromes secondary to psychological trauma. Additionally some posttraumatic syndromes may refl ect functional disruption of parietal areas. Directional or bilateral alternating peripheral sensory stimulation appear to assist in the amelioration of a wide range of clinical conditions, including the neglect syndrome and Posttraumatic Stress Disorder. It is posited that the stimulation may exert its effect through activation of parietal higher-order functions. The activation may result in an integration of sensory information and an updating of the current representation of person and space, which incorporates an awareness of current body reality, sense of self, and world view. It is hypothesized that the EMDR procedure is ideally constructed to facilitate parietal activation through multimodal sensory stimulation, attention and episodic memory retrieval and focus on internal and external body, space, and self. Further investigations and an integration of data between disciplines are suggested, in order to expand our range of effective treatments.

Resting‐state pulvinar‐posterior parietal decoupling in PTSD and its dissociative subtype

“…The superior parietal lobule (BA 5, 7) lies above the intraparietal sulcus within the posterior parietal cortex, a heteromodal association cortex integrating sensory information to construct an awareness of one's internal state, body schema, and relation to external space (Pearson, 2009). The superior parietal lobule (BA 5, 7) lies above the intraparietal sulcus within the posterior parietal cortex, a heteromodal association cortex integrating sensory information to construct an awareness of one's internal state, body schema, and relation to external space (Pearson, 2009).…”

“…Here, we demonstrate whole-brain corrected reductions in the resting-state functional connectivity of the pulvinar nuclei with parietal regions underlying multimodal sensory integration and socioaffective functions in PTSD and PTSD 1 DS. Crucially, this system displays reduced connectivity with the pulvinar in PTSD that may contribute to the altered exteroceptive capacity of these patients (Harricharan et al, 2017;Pearson, 2009). The fusing of these senses relies on thalamic nuclei to bind dispersed cortex through thalamocortical loops and this process is recursive where our working model must be continually updated as new sensations are experienced (Wolpert, Goodbody, & Husain, 1998).…”

EMDR’s Neurobiological Mechanisms of Action: A Survey of 20 Years of Searching

“…(Pearson, 2009, p. 44) This was seen to result in the movement toward a more accurate assessment of the body and self. Pearson (2009) opined that "the resolution of trauma-based symptoms occurs as updated present perceptions and an integrated sense of self replace previously held inaccurate traumatic memories and beliefs which have been stored in separate streams of consciousness" (p. 44). Therefore, she suggested that some trauma-based symptoms may be conceived of as refl ecting disruptions in parietal functions and, therefore, will respond to sensory stimulation in a manner similar to neurological syndromes of neglect.…”

“…The parietal lobe activation model (Pearson, 2009) predicts that BLS-induced stimulation of the parietal lobes facilitates the reintegration and updating of body schema and the concept of self. To date, neither direct nor indirect empirical support is available.…”

“…reciprocal inhibition/ suppression model (Corrigan, 2002;Kaye, 2007) (Richardson et al, 2009) Increased dorsolateral cortex activation (Lansing et al, 2005;Levin et al, 1999;Oh & Choi, 2007) Increased HRV/parasympathetic tone (Sack et al, 2007(Sack et al, , 2008 None to date Parietal lobe activation model (Pearson, 2009) Copyright of Journal of EMDR Practice & Research is the property of Springer Publishing Company, Inc. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use.…”