Displacement behavior is usually thought of as self-grooming, touching, or scratching, which is displayed when an animal has a conflict between two drives, such as the desire to approach an object, while at the same time being fearful of that object. With the fall of drive theory into disfavor, animal behaviorists paid little attention to displacement behavior until Maestripieri et al. (1992) pointed out that displacement behavior might be a good measure of anxiety levels. Since then a sizeable literature evaluating the effectiveness of displacement behavior measures (also called self directed behavior, or SDB) as indicators of anxiety has grown. Particularly attention has been paid to primates, including humans. Measures of displacement behavior, for example, have been applied in psychiatric studies of anxiety (Troisi et al. 2000).
Castles et al (1999) found that SDB's increased in wild olive baboons between depending on whether the nearest animal (to the animal being watched) was dominant or not. Dominant animals caused in increase in self directed behaviors by 40 %, indicating a higher level of social anxiety caused by the proximity of a dominant animal.
Chimpanzees also display higher levels of SDB's in anxiety inducing situations. Baker and Aureli (1997) found, in captive chimps, that vocalizations from animals in neighboring cages stimulated more SDB's when the chimps were housed in groups. Socially isolated chimps, however, did not respond with SDB's to vocalizations coming from neighboring cages. The vocalizations may suggest to the chimps that an attack is imminent. Baker and Aureli (1997) suggest that the isolated animals realize that no other chimps are in their cage, and consequently they feel safe even when hearing the vocalizations. Leavens et al. (2001) gave captive chimps problems of varying difficulty to solve. If their chimps started with an easy problem and then progressed to more difficult problems they displayed more SDB's when confronted with the difficult problems. Chimps who only received difficult problems did not display more SDB's. Positive auditory reinforcement during the problem reduced SDB's.
Research on animal welfare has used displacement behavior as a measure of anxiety induced by captivity or other manipulations. The effectiveness of nterventions intended to ameliorate the effects of captivity on animals may be measured by reductions in self directed behaviors.
Baker K. C., Aureli F. 1997. Behavioural indicators of anxiety: An empirical
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Castles D. L., Whiten A., Aureli F. 1999. Social anxiety, relationships and self-directed behaviour among wild female olive baboons Animal Behaviour 58: 1207-1215.
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Leavens DA, Aureli F, Hopkins WD, Hyatt CW 2001 Effects of cognitive challenge on self-directed behaviors by chimpanzees (Pan troglodytes) American Journal of Primatology 55 (1): 1-14
Maestripieri D., Schino G., Aureli F., Troisi A. 1992. A modest proposal - displacement activities as an indicator of emotions in primates. Animal Behaviour 44: (5) 967-979
Manson JH, Perry S 2000 Correlates of self-directed behaviour in wild white faced capuchins Ethology 106 (4): 301-317
Troisi A., Belsanti S., Bucci A. R., Mosco C., Sinti F., Verucci M. 2000 Affect regulation in alexithymia - An ethological study of displacement behavior during psychiatric interviews. Journal Of Nervous And Mental Disease 188: (1) 13-18
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