Thursday, December 22, 2011

A new neural correlate of consciousness?

Over at Neuroskeptic an interesting post on this paper. The overall idea of using pavlovian conditioning to test the presence of consciousness is very appealing, even if it is shown in the same paper that the Aplysia would be conscious too (and that seems unlikely, but maybe it is just a cultural bias). 
To take this approach one step forward, wouldn't be interesting to explore which widespread, conscious-related neuronal group (orexin, locus coeruleus, TMN and so on) is necessary for the trace conditioning to happen? 

Front Psychol. 2011;2:337. Epub 2011 Dec 6.

Sea slugs, subliminal pictures, and vegetative state patients: boundaries of consciousness in classical conditioning.


Cognition and Brain Sciences Unit, Medical Research Council Cambridge, UK.


Classical (trace) conditioning is a specific variant of associative learning in which a neutral stimulus leads to the subsequent prediction of an emotionally charged or noxious stimulus after a temporal gap. When conditioning is concurrent with a distraction task, only participants who can report the relationship (the contingency) between stimuli explicitly show associative learning. This suggests that consciousness is a prerequisite for trace conditioning. We review and question three main controversies concerning this view. Firstly, virtually all animals, even invertebrate sea slugs, show this type of learning; secondly, unconsciously perceived stimuli may elicit trace conditioning; and thirdly, some vegetative state patients show trace learning. We discuss and analyze these seemingly contradictory arguments to find the theoretical boundaries of consciousness in classical conditioning. We conclude that trace conditioning remains one of the best measures to test conscious processing in the absence of explicit reports.