Threat Assessment and Locomotion: Clinical Applications of an Integrated Model of Anxiety and Postural Control

Abstract

Interactions between anxiety and vestibular symptoms have been described since the late 1800s. Typically, they have been conceptualized as bidirectional effects of one condition on the other (i.e., anxiety disorders as a cause of vestibular symptoms and vestibular disorders as a cause of anxiety symptoms). Over the past 30 years, however, a steady progression of neurophysiological investigations of gait and stance under conditions of postural threat, neuroanatomical studies of connections between threat assessment and vestibular pathways in the brain, and clinical research on anxiety-related vestibular conditions has offered the building blocks of a more integrated model. In this newer concept, threat assessment is an integral component of spatial perception, postural control, and locomotion in health and disease. It is not imposed on the vestibular system from the outside or simply reactive to vestibular dysfunction, but an inherently necessary part of every aspect of mobility. In this article, the authors review evidence that supports this model and then use it to examine common neurotologic conditions in which anxiety-related processes play important roles-fear of falling, primary and secondary anxiety disorders in patients with vestibular symptoms, and chronic subjective dizziness.

Visual Dependency and Dizziness after Vestibular Neuritis

“…Interactive processes involving perceptual and psychological components are more plausible. As an example, it has been hypothesized that activation of anxiety systems by acute vertiginous states promotes prolonged overreliance on visual or somatosensory cues in vulnerable individuals [50], a concept consonant with the present results. Testing of hypotheses like this will require prospective studies that reliably measure multiple factors, including psychological measures that may contribute to poor outcomes, in a manner that will permit analyses of their interactions over time.…”

Visual Exploration during Locomotion Limited by Fear of Heights

“…This is compatible with the differential effects of exposure to heights in susceptibles and non-susceptibles to fear of heights. It is well acknowledged that anxiety-related processes affect postural control, e.g., in patients with primary and secondary anxiety disorders [7].…”

“…Self-motion has been shown to increase anxiety in patients with acrophobia during real or virtual stimulation [6]. It is well acknowledged that anxiety not only modulates postural control and locomotion [7] but also gaze and ocular motor control [8]. One of the major findings of the laboratory study of Tersteeg et al was that knowledge about the increased possibility of falling is decisive for adapting gait in an exposed situation [9].…”

What is nausea? A historical analysis of changing views

“…This schema also incorporates co-morbid balance, migraine and anxiety manifestations, due to the integral nature of vestibular, somatic, cardiovascular and visceral information in brain stem pathways (review: (Balaban et al, 2004; Staab et al, 2013)). This heuristic schema depicts the expression of signs and symptoms of nausea as an interaction between (a) a primary neurologic sensorimotor performance component that produces signs of nausea (neurologic signs domain), (b) a cognitive-behavioral component for expression of symptoms of nausea (symptom expression domain), and (c) an interoceptive or ‘bodily perception’ domain providing an interface between the two.…”