July 14, 2005
Another look at mindsight:
Last year, psychologist Ronald Rensink at the University of British Columbia proposed that some people have an alternative mode of visual experience – one that involves sensing but not ‘seeing’ – what Rensink dubbed ‘mindsight’. Now his claims have been forcefully rebutted by Daniel Simons and colleagues who argue it’s far more mundane than that: it’s all to do with how cautious people are in deciding whether or not they’ve seen something.
Rensink had performed a kind of change blindness experiment (see Hack #40) that involved participants reporting when they spotted a subtle change between two pictures. He invited participants to press one key when they ‘sensed’ a change between the pictures and to press another key only when they could ‘see’ the change and knew where and what it was. Rensink reported in Psychological Science that a subset of participants (30 %) showed evidence of what he dubbed ‘mindsight’: on a minority of trials they would report sensing the change at least a second earlier than they reported seeing it. “This mode of perception involves a conscious (or mental) experience without an accompanying visual experience”, Rensink explained. “The results presented here point towards a new mode of perceptual processing, one that is likely to provide new perspectives on the way that we experience our world”, he said.
But in this month’s issue of Psychological Science, Daniel Simons and colleagues at the University of Illinois dismiss Rensink’s findings. “Provocative claims merit rigorous scrutiny”, they said. “We rebut the existence of a mindsight mechanism by replicating Rensink’s core findings and arguing for a more mundane explanation…”.
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Simons team argue that it’s all to do with how people interpret the instructions for ‘sensing’ and ‘seeing’ – that people who show Rensink’s mindsight are trigger-happy when it comes to saying they’ve sensed a change, but very cautious when it comes to saying they’ve seen exactly what that change is. By contrast, non-mindsighters interpret 'sense' and 'see' similarly, and are far more cautious about pressing the 'sense' button. In support of this, Simons' team found that so-called mindsight participants (those sometimes showing a significant lag between sensing and seeing) were far more likely than non-mindsighters to wrongly report sensing a change on 'catch-trials' when there wasn't actually a change between the pictures. What’s more, Simons' team said, Rensink’s criteria for what constitutes mindsight are arbitrary anyway (he chose a lag of 1 second between ‘sensing’ and ‘seeing’ but if, for example, he’d chosen 1.5 seconds, far fewer subjects would have been classified as showing mindsight). All in all, mindsight is starting to look more like a guess than a new mode of seeing!
