|Welcome to Ingenpedia, The Clean Encyclopedia! You Can Edit Every Page!|
|Some jobs require working at heights.|
Acrophobia is an extreme or irrational fear or phobia of heights, especially when one is not particularly high up. It belongs to a category of specific phobias, called space and motion discomfort, that share both similar causes and options for treatment.
Most people experience a degree of natural fear when exposed to heights, known as the fear of falling. On the other hand, those who have little fear of such exposure are said to have a head for heights. A head for heights is advantageous for those hiking or climbing in mountainous terrain and also in certain jobs such as steeplejacks or wind turbine mechanics.
People with acrophobia can experience a panic attack in high places and become too agitated to get themselves down safely. Approximately 2–5% of the general population has acrophobia, with twice as many women affected as men. The term is from the Greek: ἄκρον, ákron, meaning "peak, summit, edge" and φόβος, phóbos, "fear".
Confusion with vertigo[edit | edit source]
"Vertigo" is often used (incorrectly) to describe a fear of heights, but it is more accurately a spinning sensation that occurs when one is not actually spinning. It can be triggered by looking down from a high place, by looking straight up at a high place or tall object, or even by watching something (i.e. a car or a bird) go past at high speed, but this alone does not describe vertigo. True vertigo can be triggered by almost any type of movement (e.g. standing up, sitting down, walking) or change in visual perspective (e.g. squatting down, walking up or downstairs, looking out of the window of a moving car or train). Vertigo is called height vertigo when the sensation of vertigo is triggered by heights.
Height vertigo is caused by a conflict between vision, vestibular and somatosensory senses. This occurs when vestibular and somatosensory systems sense a body movement that is not detected by the eyes. More research indicate that this conflict lead to both motion sickness and anxiety.
Causes[edit | edit source]
Traditionally, acrophobia has been attributed, like other phobias, to conditioning or a traumatic experience. Recent studies have cast doubt on this explanation. Individuals with acrophobia are found to be lacking in traumatic experiences. Nevertheless, this may be due to the failure to recall the experiences, as memory fades as time passes. To address the problems of self report and memory, a large cohort study with 1000 participants was conducted from birth; the results showed that participants with less fear of heights had more injuries because of falling. More studies have suggested a possible explanation for acrophobia is that it emerges through accumulation of non-traumatic experiences of falling that are not memorable but can influence behaviours in the future. Also, fear of heights may be acquired when infants learn to crawl. If they fell, they would learn the concepts about surfaces, posture, balance, and movement. Cognitive factors may also contribute to the development of acrophobia. People tend to wrongly interpret visuo-vestibular discrepancies as dizziness and nausea and associate them with a forthcoming fall. A traumatic conditional event of falling may not be necessary at this point.
A fear of falling, along with a fear of loud noises, is one of the most commonly suggested inborn or "non-associative" fears. The newer non-association theory is that a fear of heights is an evolved adaptation to a world where falls posed a significant danger. If this fear is inherited, it is possible that people can get rid of it by frequent exposure of heights in habituation. In other words, acrophobia could be attributed to the lack of exposure in early times. The degree of fear varies and the term phobia is reserved for those at the extreme end of the spectrum. Researchers have argued that a fear of heights is an instinct found in many mammals, including domestic animals and humans. Experiments using visual cliffs have shown human infants and toddlers, as well as other animals of various ages, to be reluctant in venturing onto a glass floor with a view of a few meters of apparent fall-space below it. Although human infants initially experienced fear when crawling on the visual cliff, most of them overcame the fear through practice, exposure and mastery and retained a level of healthy cautiousness. While an innate cautiousness around heights is helpful for survival, an extreme fear can interfere with the activities of everyday life, such as standing on a ladder or chair, or even walking up a flight of stairs. Still, it is uncertain if acrophobia is related to the failure to reach a certain developmental stage. Besides associative accounts, a diathetic-stress model is also very appealing for considering both vicarious learning and hereditary factors such as personality traits (i.e., neuroticism).
Another possible contributing factor is a dysfunction in maintaining balance. In this case the anxiety is both well founded and secondary. The human balance system integrates proprioceptive, vestibular and nearby visual cues to reckon position and motion. As height increases, visual cues recede and balance becomes poorer even in normal people. However, most people respond by shifting to more reliance on the proprioceptive and vestibular branches of the equilibrium system.
Some people are known to be more dependent on visual signals than others. People who rely more on visual cues to control body movements are less physically stable. An acrophobic, however, continues to over-rely on visual signals whether because of inadequate vestibular function or incorrect strategy. Locomotion at a high elevation requires more than normal visual processing. The visual cortex becomes overloaded, resulting in confusion. Some proponents of the alternative view of acrophobia warn that it may be ill-advised to encourage acrophobics to expose themselves to height without first resolving the vestibular issues. Research is underway at several clinics. Recent studies found that participants experienced increased anxiety not only during elevation in height, but also when they were required to move sideways in a fixed height.
A recombinant model of the development of acrophobia is very possible, in which learning factors, cognitive factors (e.g. interpretations), perceptual factors(e.g. visual dependence), and biological factors (e.g. heredity) interact to provoke fear or habituation.
Assessment[edit | edit source]
ICD-10 and DSM-V are used to diagnose acrophobia. Acrophobia Questionnaire (AQ) is a self report that contains 40 items, assessing anxiety level on a 0-6 point scale and degree of avoidance on a 0-2 point scale. The Attitude Towards Heights Questionnaires (ATHQ) and Behavioural Avoidance Tests (BAT) are also used.
However, acrophobic individuals tend to have biases in self report. They often overestimate the danger and question their abilities of addressing height relevant issues. A Height Interpretation Questionnaire (HIQ) is a self-report to measure these height relevant judgements and interpretations. The Depression Scale of the Depression Anxiety Stress Scales short form (DASS21-DS) is a self report used to examine validity of the HIQ.
Treatment[edit | edit source]
Traditional treatment of phobias is still in use today. Its underlying theory states that phobic anxiety is conditioned and triggered by a conditional stimulus. By avoiding phobic situation, anxiety is reduced. However, avoidance behaviour is reinforced through negative reinforcement. Wolpe developed a technique called systematic desensitization to help participants avoid "avoidance". Research results have suggested that even with a decrease in therapeutic contact densensitization is still very effective. However, other studies have shown that therapists play an essential role in acrophobia treatment. Treatments like reinforced practice and self-efficacy treatments also emerged.
There have been a number of studies into using virtual reality therapy for acrophobia. Botella and colleagues and Schneider were the first to use VR in treatment. Specifically, Schneider utilised inverted lenses in binoculars to "alter" the reality. Later in mid 1990s, VR became computer based and was widely available for therapists. A cheap VR equipment uses a normal PC with head-mounted display (HMD). In contrast, VRET uses an advanced computer automatic virtual environment (CAVE). VR has several advantages over in vivo treatment: (1) therapist can control the situation better by manipulating the stimuli, in terms of their quality, intensity, duration and frequency; (2) VR can help participants avoid public embarrassment and protect their confidentiality; (3) therapist's office can be well maintained; (4) VR encourages more people to seek treatment; (5) VR saves time and money as participants do not need to leave the consulting room.
Many different types of medications are used in the treatment of phobias like fear of heights, including traditional anti-anxiety drugs such as benzodiazepines, and newer options like antidepressants and beta-blockers.
Prognosis[edit | edit source]
Epidemiology[edit | edit source]
True acrophobia is uncommon.
A related, milder form of visually triggered fear or anxiety is called visual height intolerance(vHI). Up to one-third of people may have some level of visual height intolerance. Pure vHI usually has smaller impact on individuals compared to acrophobia, in terms of intensity of syptoms load, social life, and overall life quality. However, only few people with visual height intolerance seek for professional help.
Society and culture[edit | edit source]
In the Alfred Hitchcock film Vertigo, John "Scottie" Ferguson, played by James Stewart, has to resign from the police force after an incident which causes him to develop both acrophobia and vertigo. The word "vertigo" is only mentioned once, while "acrophobia" is mentioned several times. Early on in the film, Ferguson faints while climbing a stepladder. There are numerous references throughout the film to fear of heights and falling.
See also[edit | edit source]
References[edit | edit source]
- Juan, M. C.; et al. (2005). "An Augmented Reality system for the treatment of acrophobia" (PDF). Presence. 15 (4): 315–318. doi:10.1162/pres.15.4.393. S2CID 797073. Retrieved 2015-09-12. CS1 maint: discouraged parameter (link)
- Bles, Willem; Kapteyn, Theo S.; Brandt, Thomas; Arnold, Friedrich (1980-01-01). "The Mechanism of Physiological Height Vertigo: II. Posturography". Acta Oto-Laryngologica. 89 (3–6): 534–540. doi:10.3109/00016488009127171. ISSN 0001-6489. PMID 6969517.
- Whitney, Susan L.; Jacob, Rolf G.; Sparto, Patrick J.; Olshansky, Ellen F.; Detweiler-Shostak, Gail; Brown, Emily L.; Furman, Joseph M. (May 2005). "Acrophobia and pathological height vertigo: indications for vestibular physical therapy?". Physical Therapy. 85 (5): 443–458. doi:10.1093/ptj/85.5.443. ISSN 0031-9023. PMID 15842192.
- Redfern, M. S.; Yardley, L.; Bronstein, A. M. (January 2001). "Visual influences on balance". Journal of Anxiety Disorders. 15 (1–2): 81–94. doi:10.1016/s0887-6185(00)00043-8. ISSN 0887-6185. PMID 11388359.
- Coelho, Carlos M.; Waters, Allison M.; Hine, Trevor J.; Wallis, Guy (2009). "The use of virtual reality in acrophobia research and treatment". Journal of Anxiety Disorders. 23 (5): 563–574. doi:10.1016/j.janxdis.2009.01.014. ISSN 0887-6185. PMID 19282142.
- Menzies, RG; Clarke, JC. (1995). "The etiology of acrophobia and its relationship to severity and individual response patterns". Behaviour Research and Therapy. 33 (31): 499–501. doi:10.1016/0005-7967(95)00023-Q. PMID 7677717. 7677717.
- Loftus, Elizabeth F. (2016). "Memories of Things Unseen". Current Directions in Psychological Science. 13 (4): 145–147. doi:10.1111/j.0963-7214.2004.00294.x. ISSN 0963-7214. S2CID 37717355.
- Poulton, Richie; Davies, Simon; Menzies, Ross G.; Langley, John D.; Silva, Phil A. (1998). "Evidence for a non-associative model of the acquisition of a fear of heights". Behaviour Research and Therapy. 36 (5): 537–544. doi:10.1016/S0005-7967(97)10037-7. ISSN 0005-7967. PMID 9648329.
- Davey, Graham C.L.; Menzies, Ross; Gallardo, Barbara (1997). "Height phobia and biases in the interpretation of bodily sensations: Some links between acrophobia and agoraphobia". Behaviour Research and Therapy. Elsevier BV. 35 (11): 997–1001. doi:10.1016/s0005-7967(97)10004-3. ISSN 0005-7967. PMID 9431729.
- Poulton, Richie; Waldie, Karen E; Menzies, Ross G; Craske, Michelle G; Silva, Phil A (2001-01-01). "Failure to overcome 'innate' fear: a developmental test of the non-associative model of fear acquisition". Behaviour Research and Therapy. 39 (1): 29–43. doi:10.1016/S0005-7967(99)00156-4. ISSN 0005-7967. PMID 11125722.
- Eleanor J. Gibson; Richard D. Walk. "The "Visual Cliff"". Retrieved 2013-05-13. Cite journal requires
|journal=(help)CS1 maint: discouraged parameter (link)
- Campos, Joseph J.; Anderson, David I.; Barbu-Roth, Marianne A.; Hubbard, Edward M.; Hertenstein, Matthew J.; Witherington, David (2000-04-01). "Travel Broadens the Mind". Infancy. 1 (2): 149–219. doi:10.1207/S15327078IN0102_1. PMID 32680291. S2CID 704084.
- Furman, Joseph M (May 2005). "Acrophobia and pathological height vertigo: indications for vestibular physical therapy?". Physical Therapy. PMID 15842192. Archived from the original on 2007-09-26. Retrieved 2007-09-10. CS1 maint: discouraged parameter (link)
- Jacob, Rolf G; Woody, Shelia R; Clark, Duncan B.; et al. (December 1993). "Discomfort with space and motion: A possible marker of vestibular dysfunction assessed by the situational characteristics questionnaire". Journal of Psychopathology and Behavioral Assessment. 15 (4): 299–324. doi:10.1007/BF00965035. ISSN 0882-2689. S2CID 144661241.
- Brandt, T; F Arnold; W Bles; T S Kapteyn (1980). "The mechanism of physiological height vertigo. I. Theoretical approach and psychophysics". Acta Otolaryngol. 89 (5–6): 513–523. doi:10.3109/00016488009127169. PMID 6969515.
- Kitamura, Fumiaki; Matsunaga, Katsuya (December 1990). "Field Dependence and Body Balance". Perceptual and Motor Skills. 71 (3): 723–734. doi:10.2466/pms.19188.8.131.523. ISSN 0031-5125. PMID 2293175. S2CID 46272261.
- Isableu, Brice; Ohlmann, Théophile; Crémieux, Jacques; Amblard, Bernard (May 2003). "Differential approach to strategies of segmental stabilisation in postural control". Experimental Brain Research. 150 (2): 208–221. doi:10.1007/s00221-003-1446-0. ISSN 0014-4819. PMID 12677318. S2CID 32279602.
- Whitney, SL; Jacob, Rolf G; Sparto, BG (May 2005). "Acrophobia and pathological height vertigo: indications for vestibular physical therapy?". Physical Therapy. 85 (5): 443–458. doi:10.1093/ptj/85.5.443. ISSN 0031-9023. PMID 15842192.
- Coelho, Carlos M.; Santos, Jorge A.; Silva, Carlos; Wallis, Guy; Tichon, Jennifer; Hine, Trevor J. (2008-11-09). "The Role of Self-Motion in Acrophobia Treatment". CyberPsychology & Behavior. 11 (6): 723–725. doi:10.1089/cpb.2008.0023. hdl:10072/23304. ISSN 1094-9313. PMID 18991529.
- Huppert, Doreen; Grill, Eva; Brandt, Thomas (2017). "A New Questionnaire for Estimating the Severity of Visual Height Intolerance and Acrophobia by a Metric Interval Scale". Frontiers in Neurology. 8: 211. doi:10.3389/fneur.2017.00211. ISSN 1664-2295. PMC 5451500. PMID 28620340.
- Cohen, David Chestney (1977-01-01). "Comparison of self-report and overt-behavioral procedures for assessing acrophobia". Behavior Therapy. 8 (1): 17–23. doi:10.1016/S0005-7894(77)80116-0. ISSN 0005-7894.
- Steinman, Shari A.; Teachman, Bethany A. (2011-10-01). "Cognitive processing and acrophobia: Validating the Heights Interpretation Questionnaire". Journal of Anxiety Disorders. 25 (7): 896–902. doi:10.1016/j.janxdis.2011.05.001. ISSN 0887-6185. PMC 3152668. PMID 21641766.
- Abelson, James L.; Curtis, George C. (1989-01-01). "Cardiac and neuroendocrine responses to exposure therapy in height phobics: Desynchrony within the 'physiological response system'". Behaviour Research and Therapy. 27 (5): 561–567. doi:10.1016/0005-7967(89)90091-0. hdl:2027.42/28207. ISSN 0005-7967. PMID 2573337.
- Menzies, Ross G.; Clarke, J. Christopher (1995-02-01). "Danger expectancies and insight in acrophobia". Behaviour Research and Therapy. 33 (2): 215–221. doi:10.1016/0005-7967(94)P4443-X. ISSN 0005-7967. PMID 7887882.
- "APA PsycNet". psycnet.apa.org. Retrieved 2020-04-15.
- Wolpe, Joseph (1968-10-01). "Psychotherapy by reciprocal inhibition". Conditional Reflex. 3 (4): 234–240. doi:10.1007/BF03000093 (inactive 2020-11-10). ISSN 1936-3567. PMID 5712667.CS1 maint: DOI inactive as of November 2020 (link)
- Baker, Bruce L.; Cohen, David C.; Saunders, Jon Terry (February 1973). "Self-directed desensitization for acrophobia". Behaviour Research and Therapy. 11 (1): 79–89. doi:10.1016/0005-7967(73)90071-5. PMID 4781961.
- Williams, S. Lloyd; Dooseman, Grace; Kleifield, Erin (1984). "Comparative effectiveness of guided mastery and exposure treatments for intractable phobias". Journal of Consulting and Clinical Psychology. 52 (4): 505–518. doi:10.1037/0022-006X.52.4.505. ISSN 1939-2117. PMID 6147365.
- Coelho, Carlos; Alison Waters; Trevor Hine; Guy Wallis (2009). "The use of virtual reality in acrophobia research and treatment". Journal of Anxiety Disorders. 23 (5): 563–574. doi:10.1016/j.janxdis.2009.01.014. PMID 19282142.
- Emmelkamp, Paul; Mary Bruynzeel; Leonie Drost; Charles A. P. G van der Mast (1 June 2001). "Virtual Reality Treatment in Acrophobia: A Comparison with Exposure in Vivo". CyberPsychology & Behavior. 4 (3): 335–339. doi:10.1089/109493101300210222. PMID 11710257.
- Botella, C.; Baños, R. M.; Perpiñá, C.; Villa, H.; Alcañiz, M.; Rey, A. (1998-02-01). "Virtual reality treatment of claustrophobia: a case report". Behaviour Research and Therapy. 36 (2): 239–246. doi:10.1016/S0005-7967(97)10006-7. ISSN 0005-7967. PMID 9613029.
- Krijn, Merel; Emmelkamp, Paul M. G; Biemond, Roeline; de Wilde de Ligny, Claudius; Schuemie, Martijn J; van der Mast, Charles A. P. G (2004-02-01). "Treatment of acrophobia in virtual reality: The role of immersion and presence". Behaviour Research and Therapy. 42 (2): 229–239. doi:10.1016/S0005-7967(03)00139-6. ISSN 0005-7967. PMID 14975783.
- Choi, Young H.; Jang, Dong P.; Ku, Jeong H.; Shin, Min B.; Kim, Sun I. (2001-06-01). "Short-Term Treatment of Acrophobia with Virtual Reality Therapy (VRT): A Case Report". CyberPsychology & Behavior. 4 (3): 349–354. doi:10.1089/109493101300210240. ISSN 1094-9313. PMID 11710259.
- Morina, Nexhmedin; Ijntema, Hiske; Meyerbröker, Katharina; Emmelkamp, Paul M. G. (2015-11-01). "Can virtual reality exposure therapy gains be generalized to real-life? A meta-analysis of studies applying behavioral assessments". Behaviour Research and Therapy. 74: 18–24. doi:10.1016/j.brat.2015.08.010. ISSN 0005-7967. PMID 26355646.
- Arroll, Bruce; Wallace, Henry B.; Mount, Vicki; Humm, Stephen P.; Kingsford, Douglas W. (2017-04-03). "A systematic review and meta-analysis of treatments for acrophobia". The Medical Journal of Australia. 206 (6): 263–267. doi:10.5694/mja16.00540. ISSN 1326-5377. PMID 28359010. S2CID 9559825.
- Huppert, Doreen; Grill, Eva; Brandt, Thomas (2013-02-01). "Down on heights? One in three has visual height intolerance". Journal of Neurology. 260 (2): 597–604. doi:10.1007/s00415-012-6685-1. ISSN 1432-1459. PMID 23070463. S2CID 21302997.
- Kapfhammer, Hans-Peter; Fitz, Werner; Huppert, Doreen; Grill, Eva; Brandt, Thomas (2016). "Visual height intolerance and acrophobia: distressing partners for life". Journal of Neurology. 263 (10): 1946–1953. doi:10.1007/s00415-016-8218-9. ISSN 0340-5354. PMC 5037147. PMID 27383642.
[edit | edit source]