Binocular and Monocular Coincidence-Anticipation Timing Responses

Background Coincidence-anticipation timing (CAT) responses require individuals to determine the time at which an approaching object will arrive at (time to collision) or pass by (time to passage) the observer and to then make a response coincident with this time. Previous studies suggest that under some conditions time to collision estimates are more accurate when binocular and monocular cues are combined. The purpose of this study was to compare binocular and monocular coincidence anticipation timing responses with the Bassin Anticipation Timer, a device for testing and training CAT responses. Methods: Useable data were obtained from 20 participants. Coincidence-anticipation timing responses were determined using a Bassin Anticipation Timer over a range of approaching stimulus linear velocities of 5 to 40mph. Participants stood to the left side of the Bassin Anticipation track. The track was below eye height. The participants’ task was to push a button to coincide with arrival of the approaching stimulus at a location immediately adjacent to the participant. CAT responses were made under three randomized conditions: binocular viewing, monocular dominant eye viewing, and monocular non-dominant eye viewing. Results: Signed (constant), unsigned (absolute), and variable (standard deviation) CAT response errors were determined and compared across viewing conditions at each stimulus velocity. There were no significant differences in CAT errors between the conditions at any stimulus velocity, although the differences in signed and unsigned errors approached significance at 40mph. Conclusions: The addition of binocular cues did not result in a reduction in coincidence anticipation timing response errors compared to the monocular viewing conditions. There were no differences in CAT response errors between the monocular dominant eye viewing and monocular non-dominant eye viewing conditions.