Patients in a minimally conscious state (MCS) - those with severe brain damage who demonstrate intermittent awareness of their environment - may retain some degree of cognitive function, even though they can’t follow simple instructions or communicate, the findings from a small study suggest.

Using a special type of “functional” MRI scan, researchers found that such patients exhibit brain responses to speech similar to those seen in healthy individuals. The findings appear in the medical journal Neurology

“These findings raise important questions related to whether MCS patients have a greater capacity to experience subjective states but also to benefit from therapeutic interventions,” Dr. Joy Hirsch, at Columbia University in New York, and her colleagues suggest in their report.

Hirsch’s group performed functional MRI on two brain-injured patients in a minimally conscious state and on seven healthy subjects as they listened to narratives by family members. Functional MRI was also performed while the subjects’ hands were touched.

“The MCS patients studied here showed remarkably similar brain activity to that evoked in healthy control subjects,” the authors report.

“In our subjects, the resting MCS brain preserves an ability to recruit (nerve) networks necessary for cognition and interaction,” Hirsch’s group reports. This possibility “presents a humanitarian imperative to further investigate the state of consciousness of these and other brain-injured patients.”

SOURCE: Neurology, February 8, 2005.