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Preclinical prediction of autistic spectrum disorders (ASD) is one of the priorities of current research. Children at risk of ASD develop an atypical visual perception profile early in their lives, which influences their visual responsiveness, distribution of attention, and social orienting. In this study we have compared the oculomotor behavior in an infant at familial risk of ASD with data from two 10-month infants with typical development. The SMI RED500 eye tracker was used for acquisition. Most parameters of visual perception in the at-risk infant were found to differ significantly from these of the controls. The strategy of visual search in the at-risk infant was generally less successful (13% of attempts vs 31% and 56% in the controls) with a tendency to focus predominantly on social stimuli (50% of the total gaze time). The said changes together with longer fixation duration (576.41 ms vs 527.77 and 386.72 ms in the two controls), lower saccadic frequency (1.74 counts/ms vs 1.84 and 2.18 counts/ms), and shorter scan path length (2774.24 px vs 3612.58 and 3985.43 px) may result in difficulties in switching tasks and processing information.

Cervico-vestibulo-oculomotor interactions in patients with Parkinson disease stages III-IV and healthy subjects were studied in horizontal head movement and gaze fixation on immobile and mobile targets. Significant changes in the amplitude, head movement frequency and asymmetry, eye movement amplitude, and phase mismatch between head and eye movements were revealed in patients in comparison to the normal.

We studied the interaction of the oculomotor, cervical, and vestibular systems using a specially developed technique. A series of two tests were performed on 26 healthy subjects and 42 patients with stages I-II Parkinson's disease receiving and not receiving treatment. In coordinated tests, all amplitude-time characteristics of patients significantly differed from those in healthy subjects. Possible mechanisms of cervico-vestibular-oculomotor disorders are discussed.

Results of Russian-Austrian space experiment "Monimir" which was a part of international space program "Austromir" are presented in this paper. Characteristics of horizontal gaze fixation reaction (hGFR) to visual targets were analyzed. Seven crewmembers of "Mir" space station expeditions took part in the experiment. Experiments were carried out 4 times before space flight, 5 times in flight and 3-4 times after landing. There were revealed significant alterations in characteristics of gaze fixation reaction during flight and after its accomplishing, namely: an increase of the time of gaze fixation to the target, changes of eye and head movements' velocity and increase of the gain of vestibular-ocular reflex, that pointed out to the disturbances of the control mechanisms of vestibular-ocular reflex in weightlessness caused by changes of vestibular input's activity. There was discovered also the difference in the strategies of adaptation to microgravity conditions among the cosmonauts of flight and non-flight occupation: in the first group exposure to weightlessness was accompanied by gaze hypermetry and inhibition of head movements; in the second one--on the contrary--by increase of head movement velocity and decrease of saccades' velocity.

Dogs were trained for tonic forelimb flexion fixed to a lever in order to hold a cup with meat during eating, when the head was bent down to a foodwell. Before learning, the forelimb flexion is accompanied by the anticipatory lifting of the head bent down to the foodwell; following lowering of the head leads to an extension of the flexed forelimb. Simultaneous holding of the flexed forelimb and lowered head is achieved by learning. During the original learning, the innate head-forelimb coordination was rearranged into the opposite one. After the initial instrumental learning, the "working" forelimb was changed to test whether a transfer of the learned head-forelimb coordination would occur. It was shown that the execution of the instrumental reaction by the untrained forelimb was impossible, because the innate coordination between the head and this forelimb persisted. It could also be rearranged by learning. The involvement of the motor cortex in the unilateral rearrangement of the innate head-forelimb movement coordination is discussed.

Dogs were trained to remove a cup with meat to the head bent down to the feeder and hold the limb flexed during eating. At the early stage of learning, the stable innate head-forelimb coordination characteristic for untrained animals was manifest. The forelimb flexion was accompanied by anticipatory lifting of the bent head, and the following bending of the head led to an extension of the flexed forelimb. The opposite coordination, i.e., the lifting and holding of the forelimb when the head is bent down, was achieved only by training. The lesion of the motor cortex contralateral to the working forelimb in the trained dogs led to a prolonged disturbance of the simultaneous holding of the flexed forelimb and the head bent down. The lesion of the motor cortex did not affect the individual movements but disturbed their coordination. In the operated dogs the innate relationships between the head and forelimb movement recovered. The results support the previous finding that the lesion of the motor cortex led to recovery of the innate coordination transformed in the process of learning.