[Stabilization of the gaze in chameleons: visual and vestibular reflexes].
Some visual, vestibular and proprioceptive reflexes which contribute to gaze (head + eye) stabilization were quantified in the chameleon. All the reflexes were analysed in the horizontal plane, and the visual reflexes were also studied in the vertical plane. In restrained-head animals, both the optokinetic nystagmus (OKN) and the vestibulo-ocular reflex (VOR) had low gains. In free-head animals, the head (opto-collic or vestibulo-collic reflex) and eye (OKN or VOR) responses added their effects, thus improving gaze stabilization, especially during vestibular stimulation. Cervical stimulation provoked both a cervico-ocular reflex (COR) in the compensatory direction and a large number of saccades. The saccadic response was especially marked in the presence of patterned visual surroundings.
Bennis
M
M
Département de Biologie, Faculté des Sciences, Université Cadi Ayyad, Marrakech, Maroc.
Sansonetti
A
A
Gioanni
H
H
D000818:Animals; D005133:Eye Movements / Q000502:physiology; D005403:Fixation, Ocular / Q000502:physiology; D008116:Lizards / Q000502:physiology*; D009760:Nystagmus, Physiologic / Q000502:physiology*; D012027:Reflex, Vestibulo-Ocular / Q000502:physiology*
Stabilisation du regard chez le caméléon: réflexes visuels et vestibulaires.