A recent study published in the New England Journal of Medicine (NEJM), provided the largest-ever investigation of patients with disorders of consciousness who demonstrate hidden high-level cognitive function. The term now applied to such persons is “cognitive motor dissociation” (CMD). CMD is seen in patients with more extensive brain injuries who otherwise seem mostly or entirely unaware of their surroundings yet can perform sustained cognitive work in response to commands that can be detected using functional magnetic resonance imaging (fMRI) or electroencephalography (EEG) techniques. The CTSC at Weill Cornell Medicine began supporting the work leading to these results as far back as 1994 when (as the GCRC) the first IRB proposal to use scatter beds for patient studies was submitted and developed. Over the thirty year period of subsequent research by the research team under the direction of Dr. Nicholas Schiff at the Weill Medical College (WMC) many seminal findings concerning recovery of brain function following coma have emerged from these studies. However, the recent study is by far the most significant result as it spans studies across six major international medical centers in a consortium developed by Dr. Schiff and funded by the James S. McDonnell Foundation in 2008. As part of the evolution of the work Dr. Schiff’s team formed a parallel collaboration with the Rockefeller University CTSC and began admitting in-patients at the Rockefeller University Hospital in 2012. The two CTSCs have functioned as a co-operative platform to ensure that all patients screened for studies can be evaluated, with patients requiring more monitoring and medical attention undergoing in-patient admission at WMC and those able to have longer monitored stays admitted to the Rockefeller University Hospital (RUH). Imaging using magnetic resonance imaging (MRI) and positron emission tomography (PET) studies has been carried out at the WMC CITI for all participants.
The result of the recent NEJM study revealed that of 241 patients who were unresponsive to bedside commands, when they were asked to carry out complex mental work, 25% had sustained and relevant cognitive responses as shown on EEG readouts or fMRI. In the United States alone, the number of people estimated to be in a chronic vegetative state ranges from 5,000–42,000, while those in a minimally conscious state are estimated to range from 112,000 to 280,000. The findings indicate that many seemingly unconscious patients may be aware and capable of cognition. These findings are spurring several new lines of research and the team hopes to begin studying more efficient methods for detecting cognitive motor dissociation in a greater variety of clinical settings and to aim now at new first-in human studies to bring state-of-the-art brain computer interface technologies to CMD patients to try to re-establish their ability to communicate with the outside world.
Dr. Nicholas Schiff, the Jerold B. Katz Professor of Neurology and Neuroscience at the Feil Family Brain and Mind Research Institute at Weill Cornell Medicine (WCM), along with his colleagues at Mount Sinai has made a significant discovery. Supported by the CTSC, the study published on August 14 in the New England Journal of Medicine reveals that some patients with severe brain injuries exhibit clear signs of cognitive function in response to commands, as detected by brain scans, even when they are unable to move or speak.
This study, the largest-ever investigation into cognitive-motor dissociation, analyzed 241 patients in a coma or vegetative state who were unable to visibly respond to bedside commands. Remarkably, one-fourth of these patients demonstrated sustained and relevant cognitive responses, as shown by EEG or fMRI scans.
Dr. Schiff noted, "Just knowing that a patient has this ability to respond cognitively can be a game-changer in terms of life-support decisions and the degree of engagement from caregivers and family members."
