Misperceptions and hallucinatory experiences in ultra-trailer, high-altitude runners.

Background: The Mountain Activities Neuro-behavioural Research Programme is a research project born in the 2 nd Unit of Psychiatry, Department of Clinical and Experimental Medicine at the University of Pisa to investigate the effects of altitude on the mental and neuro-behavioural aspects of people performing activities in mountainous areas.

Methods: In this study, after elaborating a standardised data collection form, based on traditional psychopathology notions, to classify the misperceptions reported by the athletes taking part, we investigated the various types of these misperceptions in 21 athletes (including only one female), with a mean age of 44.90 ± 8.51 (min 33 and max 58).

Results: The athletes reported different kinds of misperceptions. It was possible to highlight three different clusters of athletes, based on the similarities between the kinds of misperceptions reported in each cluster: (a) anomalies in the intrinsic characteristics of perceptions (i.e. depersonalisation and derealisation), (b) illusions and (c) hallucinations.

Conclusions: This study supports the concept that anomalous perceptual experiences may occur independently of the context of psychiatric or neurological disorders. The chance of observing hallucinatory phenomena outside the context of psychiatric disorders and in extreme environmental conditions among ultra-trail runners may offer a unique opportunity to those intending to study psychopathological conditions in a 'para-physiological' context.