Controlling attentional priority by preventing changes in oculomotor programs: a job for the premotor cortex?

Abruptly presented items capture attention automatically so they constitute the first items to be examined [Yantis and Jonides, Journal of Experimenta l Psychology: Human Perception and Performance, 1984.10:601: Jonids and Yan tis, Perception and Psychophysics, 1988;43:346; Theeuwes, Perception and Ps ychophysics, 1992:51:599: Theeuwes, Journal or Experimental Psychology: Hum an Perception and Performance, 1994;20:799]. This attentional priority can be controlled in a top down manner by directing attention towards the locus of interest [Yantis and Johnson, Journal of Experimental Psychology: Human Perception and Performance, 1990;16:812; Theeuwes. Perception and Psychoph ysics, 1991:49:83, Miller, Perception and Psychophysics, 1989;45:567; Folk et al., Journal of Experimental Psychology: Human Perception and Performanc e, 1992: 18:1030]. The premotor theory of attention [Rizzolatti et al., Neu ropsychologia 1987;25:31; Rizzolatti et al., Attention and Performance XV, 1994, p. 231] assumes that the mechanism responsible for the attentional sh ifts is strictly linked to that responsible for eye movements, and several studies [Corbetta et al., Society of Neuroscience Abstracts 1997,23:122.12, Nobre ct al., Brain 1997;120:515. Theeuwes et al., Journal of Experimental Psychology: Human Perception and Performance, 1999;25:1595] suggested that the premotor cortex plays a role in the control of attention. However, the nature of this involvement is Still unclear. We have been asking a patient (RJ) with a damage of the right premotor cortex to decide whether a target had a discontinuity on its right or left side. The absolute location of th e target was pre-cued. In Section 2, an interference was observed when ZI S udden onset occurred in the visual space, suggesting that RJ was not able t o control attentional capture. The possibility to attribute this interferen ce to an insufficient focalization of attention or a grouping effect were d iscarded by Sections 3 and 4. respectively. Section 5 revealed that this in terference followed exclusively the onset occurring in the hemifield opposi te the one containing the target (meridian effect [Rizzolatti et al., Neuro psychologia 1987;25:31]). The results suggest that the control of attention al Capture may be achieved by keeping constant the parameters of the approp riate oculomotor program. (C) 2001 Elsevier Science Ltd. All rights reserve d.