Lateralized reaching as dynamical symmetry breaking in the bushbaby (Otolemur garnettii): preliminary evidence.
Eight bushbabies were subjected to an extensive series of hand preference trials in which they were required to reach for a raisin from a rotating platform approaching from the right- or left-hand side of their visual field. Three principal types of behavior were observed. Several individuals known to be stable in hand preference continued to show a strong preference for a single hand. Another group, including some previously categorized as stable, exhibited "ambidextrous" cross-body reaching behavior. One individual exhibited far more complex behavior, being ambidextrous at low and very high speeds but lateralized at intermediate speeds. A straightforward adaptation of the dynamical neural field theory of Schöner et al. (1997) provides a model allowing each type of behavior, except possibly the shift from lateralized behavior to ambidextrous behavior at high speed, which might nonetheless be accommodated with minor modification.
Cantalupo
Claudio
C
Department of Psychology, The University of Memphis, USA. ccantal@rmy.emory.edu
Ward
Jeannette P
JP
Franceschetti
Donald R
DR
D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D001921:Brain / Q000502:physiology*; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D005701:Galago / Q000502:physiology*; D008297:Male; D008960:Models, Psychological; D011597:Psychomotor Performance / Q000502:physiology*; D014794:Visual Fields / Q000502:physiology