Time-Window-of-Integration (TWIN) Model for Saccadic Reaction Time: Effect of Auditory Masker Level on Visual–Auditory Spatial Interaction in Elevation
- 151 Downloads
Saccadic reaction time (SRT) to a visual target tends to be shorter when auditory stimuli are presented in close temporal and spatial proximity, even when subjects are instructed to ignore the auditory non-target (focused attention paradigm). Previous studies using pairs of visual and auditory stimuli differing in both azimuth and vertical position suggest that the amount of SRT facilitation decreases not with the physical but with the perceivable distance between visual target and auditory non-target. Steenken et al. (Brain Res 1220:150–156, 2008) presented an additional white-noise masker background of three seconds duration. Increasing the masker level had a diametrical effect on SRTs in spatially coincident versus disparate stimulus configurations: saccadic responses to coincident visual–auditory stimuli are slowed down, whereas saccadic responses to disparate stimuli are speeded up. Here we show that the time-window-of-integration model accounts for this observation by variation of a perceivable-distance parameter in the second stage of the model whose value does not depend on stimulus onset asynchrony between target and non-target.
KeywordsMultisensory integration Saccadic reaction time Auditory masker
This research was supported by Grants from Deutsche Forschungsgemeinschaft Di 506/8-1 and Di 506/8/-3 and SFB-TR31 (Active Listening).
- Blauert J (1997) The psychophysics of human sound localization 2nd edn. MIT Press, CambridgeGoogle Scholar
- Diederich A, Colonius H (2004) Modeling the time course of multisensory interaction in manual and saccadic responses. In: Calvert G, Spence C, Stein BE (eds) Handbook of multisensory processes. MIT Press, CambridgeGoogle Scholar
- Heuermann H, Colonius H (2001) Spatial and temporal factors in visual–auditory interaction. In: Sommerfeld E, Kompass R, Lachmann T (eds) Proceedings of the 17th meeting of the international society for psychophysics. Pabst Science, Lengerich, pp 118–123Google Scholar
- Meredith MA, Nemitz JW, Stein BE (1987) Determinants of multisensory integration in superior colliculus neurons. I. Temporal factors. J Neurosci 10:3215–3229Google Scholar
- Munoz DP, Schall JD (2004) Concurrent, distributed control of saccade initiation in the frontal eye field and superior colliculus. In: Hall WC, Moschovakis A (eds) The superior colliculus: new approaches for studying sensorimotor integration. CRC Press, Boca Raton, pp 55–82Google Scholar
- Stein BE, Meredith MA (1993) The merging of the senses. The MIT Press, CambridgeGoogle Scholar
- Van Opstal AJ, Munoz DP (2004) Auditory–visual interactions subserving primate gaze orienting. In: Calvert G, Spence C, Stein BE (eds) Handbook of multisensory processes, Cambridge, MIT Press, pp 373–393Google Scholar