Fig. 4. Mean gain of the OCR obtained for different behavioural conditions, in response to increasing stimuli velocity step. (A) Gains obtained in the `resting', `standing' and `flying' conditions. The gain was progressively increased in the higher velocity range of stimuli for each of these three conditions. (B) Mean gain obtained for the `standing condition' in the presence of and without a frontal airflow. The corresponding gain curves were not different. Each point is the mean value ± s.e.m. (N=12) of responses obtained in the clockwise and anticlockwise directions.