Last summer Soazig and I were approached about writing a review article on oculomotor readiness hypothesis / premotor theory for a special issue of Vision on “Eye Movements and Visual Cognition”. This was a very tempting opportunity, and I must admit I was flattered to be courted by psychology bigwigs like Klein and Liversedge, but I had a couple of reservations. Firstly, this is quite a crowded field, and there had already been some excellent reviews of the literature, including one I had written with Thomas Schenk just a few years ago. Did we really have something new to say? Could we produce something that offered more insight than just describing recent developments in the field? Secondly, writing any paper is time consuming, but with the pressures of the imminent REF there is a distinct disincentive to publishing papers that are not eligible for submission, such as review papers. On the flip side, writing a review seemed like a a great opportunity to articulate the theoretical ideas about attention and eye-movements that we had been bubbling around over the last few years and in the end the decision was easy.
We spent quite some time kicking round ideas for a structure and two key concepts formed the basis of the review. Firstly, that it was absolutely critical to explicitly a differentiate between presaccadic attention, covert endogenous attention and covert exogenous attention. Secondly, that the evidence from neuropsychological studies had been rather neglected in favour of psychophysical or neurophysiological evidence. Once we had these ideas, the review started to fall into place and we were able to develop our key lines of argument, which were (1) presaccadic attention is qualitatively different from covert attention, so studies of presaccadic attention don’t speak to oculomotor readiness / premotor theory per se (2) The neuropsychological evidence for a mandatory coupling between covert exogenous orienting and saccade programming is pretty strong, but the evidence is actually really weak for a causal link between endogenous attention and saccade programming. In the end we felt convinced that the evidence was most convincing for an oculomotor readiness theory of exogenous orienting, (hence the snazzy acronym of OREO) and we hope you will read the paper and be convinced too!
The paper is open access, and you can find it here: https://www.mdpi.com/2411-5150/3/2/17/htm
Casteau, S & Smith, D.T. (2019). Associations and Dissociations between Oculomotor Readiness and Covert Attention. Vision 3: 17.
Writing this review has been an interesting process, as it touches on some conceptual issues that Soazig and I have been struggling with over the last few years. One thing I have never understood is why saccade deviation away from an attended location is often cited as evidence for premotor theory. Everyone says it, but it makes no sense! Surely the saccade should be deviated towards the attended location if it’s associated with a saccade programme? Maybe now someone will explain it to me at our upcoming workshop on attention and motor control (all welcome 😊): http://motorbiasproject.com/workshop