Effects of isolated and combined spatial and temporal attention on temporal resolution

Attention in daily life must be oriented in space and time in order to ensure adaptive behavior like when catching a ball. Previous work showed that while spatial and temporal attention can operate independently under low task demands, synergistic effects might depend on the higher perceptual demands of the task to be performed. However, this latter conclusion is limited so far to situations in which task requirements stress spatial processing. In this case, it seems that temporal attention effects occur only at attended, but not unattended, spatial locations. Here, we investigated the relation between spatial and temporal attention using a task that required more temporal than spatial processing. Participants performed spatial and temporal orienting tasks either separately or in a combined spatiotemporal session. The task was to judge if there was a small gap between two sequential stimuli or not. Endogenous central cues (shapes or colors) preceded target presentation by signaling either the spatial location and/or the timing at which stimuli could occur. Results showed significant spatial orienting effects in both separate and combined sessions, implying more efficient temporal resolution processes for valid spatial trials as compared to neutral (session 1) and invalid trials (session 2). Conversely, temporal orienting effects were absent in both separate and combined sessions and, more importantly, they did not interact with spatial attention as shown in previous studies. Overall, these findings suggest that spatial cues are more effective than temporal cues in improving temporal resolution processes.