More Free Willish Goodness from Science
More Free Willish Goodness from Science -
The Libet studies, which have caused such a stir, apparently demonstrated that conscious choice lags behind by neural activity by around one third of a second. One of my favorite responses to these studies - Dennett's - argues that the notion we can perform simultaneity judgments as to neural events and volitions depends upon the idea of the Cartesian Theatre, a place in the brain where everything comes together. But while that response looks plausible for a lag of one third of a second, it doesn't look quite so plausible when the gap is an enormous 7 seconds. That's the claim of a new study just published in Nature Neuroscience.
In the study, subjects engaged in a free choice task, choosing between pressing a button with their left or their right hands. The researchers found that they could predict with 60% accuracy which hand they would choose, a full 7 (and up to 10) seconds before the subject reported that the decision was made, by analysing activity in the PFC. The popular presentations of this study have not failed to draw the conclusion that this study threatens free will.
One comment: I don't see why we shouldn't interpret the PFC activity as representing a disposition and not a choice (though PFC is involved in high level planning).