Acrophobia and visual height intolerance: advances in epidemiology and mechanisms

Abstract

Historical descriptions of fear at heights date back to Chinese and Roman antiquity. Current definitions distinguish between three different states of responses to height exposure: a physiological height imbalance that results from an impaired visual control of balance, a more or less distressing visual height intolerance, and acrophobia at the severest end of the spectrum. Epidemiological studies revealed a lifetime prevalence of visual height intolerance including acrophobia in 28% of adults (32% in women; 25% in men) and 34% among prepubertal children aged 8–10 years without gender preponderance. Visual height intolerance first occurring in adulthood usually persists throughout life, whereas an early manifestation in childhood usually shows a benign course with spontaneous relief within years. A high comorbidity was found with psychiatric disorders (e.g. anxiety and depressive syndromes) and other vertigo syndromes (e.g. vestibular migraine, Menière’s disease), but not with bilateral vestibulopathy. Neurophysiological analyses of stance, gait, and eye movements revealed an anxious control of postural stability, which entails a co-contraction of anti-gravity muscles that causes a general stiffening of the whole body including the oculomotor apparatus. Visual exploration is preferably reduced to fixation of the horizon. Gait alterations are characterized by a cautious slow walking mode with reduced stride length and increased double support phases. Anxiety is the critical factor in visual height intolerance and acrophobia leading to a motor behavior that resembles an atavistic primitive reflex of feigning death. The magnitude of anxiety and neurophysiological parameters of musculoskeletal stiffening increase with increasing height. They saturate, however, at about 20 m of absolute height above ground for postural symptoms and about 40 m for anxiety (70 m in acrophobic participants). With respect to management, a differentiation should be made between behavioral recommendations for prevention and therapy of the condition. Recommendations for coping strategies target behavioral advices on visual exploration, control of posture and locomotion as well as the role of cognition. Treatment of severely afflicted persons with distressing avoidance behavior mainly relies on behavioral therapy.

The Effects of Virtual Height Exposure on Postural Control and Psychophysiological Stress Are Moderated by Individual Height Intolerance

“…To maintain proper balance and produce corresponding postural commands is especially challenging for people with fear of heights. About 30% of the adult population suffers from visual height intolerance, which reduces quality of life, causes behavioural constraints and avoidance of exposure to heights ( Huppert et al, 2020 ). When exposed to heights, these individuals typically show anxiety, vertigo, unsteadiness, postural imbalance and gait insecurity, inner agitation, rapid heartbeat, sweating, drowsiness, and tremor ( Huppert et al, 2020 ).…”

“…About 30% of the adult population suffers from visual height intolerance, which reduces quality of life, causes behavioural constraints and avoidance of exposure to heights ( Huppert et al, 2020 ). When exposed to heights, these individuals typically show anxiety, vertigo, unsteadiness, postural imbalance and gait insecurity, inner agitation, rapid heartbeat, sweating, drowsiness, and tremor ( Huppert et al, 2020 ). The most common trigger situations of these symptoms are looking down from towers, hiking and mountaineering, climbing ladders, walking over a bridge, and looking down from a high-rise window ( Brandt et al, 2015 ; Huppert et al, 2020 ).…”

“…When exposed to heights, these individuals typically show anxiety, vertigo, unsteadiness, postural imbalance and gait insecurity, inner agitation, rapid heartbeat, sweating, drowsiness, and tremor ( Huppert et al, 2020 ). The most common trigger situations of these symptoms are looking down from towers, hiking and mountaineering, climbing ladders, walking over a bridge, and looking down from a high-rise window ( Brandt et al, 2015 ; Huppert et al, 2020 ). Height intolerance is thought to originate from an interaction between the psychological factors, mainly anxiety, and the physiological factors, such as a discrepancy between the visual, vestibular and somatosensory information used for the postural control ( Teggi et al, 2019 ).…”

Seltenere, aber klinisch relevante episodische Schwindelsyndrome

“…So werden therapeutisch zum einen Verhaltensanweisungen zur Vorbeugung und zum anderen Ratschläge/Maßnahmen zur Therapie einer manifesten visuellen Höhenintoleranz oder Akrophobie angewandt. Basierend auf Studien zur Abhängigkeit des Höhenschwindels von der Körperhaltung [54] sowie auf den neurophysiologischen Veränderungen in Höhe dienen Verhaltensanweisungen als Strategie zur Verminderung der individuellen visuellen Höhenintoleranz und Akrophobie und betreffen die visuelle Exploration, die Körperhaltung und den Gang [55] (▶Tabelle 2). Außerdem sind kognitive Doppelaufgaben (‚dual tasking') bei anfälligen Individuen unter Höhenexposition wirksam [50,51].…”

Virtual Reality Exposure Therapy for Fear of Heights: Clinicians’ Attitudes Become More Positive After Trying VRET

“…About one third of the population suffers from susceptibility to acrophobia (fear of heights) and visual height intolerance (Huppert et al, 2020). For the purposes of this study, fear of heights is regarded as an inter-and intra-individual continuum of varying degrees of discomfort that may be elicited by visual heights.…”