“ Our study shows that it may be possible to screen for hidden consciousness using widely available structural brain imaging , moving the detection of CMD one step closer to general clinical use .”
Issue 34.1 WINTER 2025
But the precise pathways in the brain that become disrupted in this condition were unknown .
In the new study , the researchers used EEG to examine 107 brain injury patients . The technique can determine when patients are trying , though unable , to respond to a command such as “ keep opening and closing your right hand .”
The analysis detected CMD in 21 of the patients .
The researchers then analyzed structural MRI scans from all of the patients .
“ Using a technique we developed called bi-clustering analysis , we were able to identify patterns of brain injury that are shared among patients with CMD and contrast to those without CMD ,” says co-lead author Qi Shen , PhD , associate research scientist in the Claassen lab and an expert in signal processing , machine learning , and biostatistics .
The researchers found that all of the CMD patients had intact brain structures related to arousal and command comprehension , supporting the notion that these patients were hearing and understanding the commands but were unable to carry them out .
“ We saw that all of the CMD patients had deficits in brain regions responsible for integrating comprehended motor commands with motor output , preventing CMD patients from acting on verbal commands ,” says Claassen .
The findings may allow researchers to better understand which brain injury patients have CMD , which will be useful for clinical trials that support recovery of consciousness .
More research is required before these approaches can be applied to clinical practice . “ However , our study shows that it may be possible to screen for hidden consciousness using widely available structural brain imaging , moving the detection of CMD one step closer to general clinical use ,” Claassen says .
“ Not every critical care unit may have resources and staff that is trained in using EEG to detect hidden consciousness , so MRI may offer a simple way to identify patients who require further screening and diagnosis .” g
“ Our study shows that it may be possible to screen for hidden consciousness using widely available structural brain imaging , moving the detection of CMD one step closer to general clinical use .”
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