TY - JOUR
T1 - Preserved feedforward but impaired top-down processes in the vegetative state
AU - Boly, Melanie
AU - Garrido, Marta Isabel
AU - Gosseries, Olivia
AU - Bruno, Marie Aurélie
AU - Boveroux, Pierre
AU - Schnakers, Caroline
AU - Massimini, Marcello
AU - Litvak, Vladimir
AU - Laureys, Steven
AU - Friston, Karl
PY - 2011/5/13
Y1 - 2011/5/13
N2 - Frontoparietal cortex is involved in the explicit processing (awareness) of stimuli. Frontoparietal activation has also been found in studies of subliminal stimulus processing. We hypothesized that an impairment of top-down processes, involved in recurrent neuronal message-passing and the generation of long-latency electrophysiological responses, might provide a more reliable correlate of consciousness in severely brain-damaged patients, than frontoparietal responses. We measured effective connectivity during a mismatch negativity paradigm and found that the only significant difference between patients in a vegetative state and controls was an impairment of backward connectivity from frontal to temporal cortices. This result emphasizes the importance of top-down projections in recurrent processing that involve high-order associative cortices for conscious perception.
AB - Frontoparietal cortex is involved in the explicit processing (awareness) of stimuli. Frontoparietal activation has also been found in studies of subliminal stimulus processing. We hypothesized that an impairment of top-down processes, involved in recurrent neuronal message-passing and the generation of long-latency electrophysiological responses, might provide a more reliable correlate of consciousness in severely brain-damaged patients, than frontoparietal responses. We measured effective connectivity during a mismatch negativity paradigm and found that the only significant difference between patients in a vegetative state and controls was an impairment of backward connectivity from frontal to temporal cortices. This result emphasizes the importance of top-down projections in recurrent processing that involve high-order associative cortices for conscious perception.
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U2 - 10.1126/science.1202043
DO - 10.1126/science.1202043
M3 - Article
C2 - 21566197
AN - SCOPUS:79956053706
VL - 332
SP - 858
EP - 862
JO - Science
JF - Science
SN - 0036-8075
IS - 6031
ER -