Brain Response to One's Own Name in Vegetative State, Minimally Conscious State, and Locked-in Syndrome

TLDR

Estimating residual perception in severely brain‑injured patients with altered consciousness is a major challenge. The study examined whether patients in vegetative state, minimally conscious state, and locked‑in syndrome can detect their own name. Auditory evoked potentials to the patient’s own name and seven other first names were recorded in 15 brain‑damaged patients. A P3 component was elicited by the patient’s name in all locked‑in syndrome and minimally conscious patients and in 3 of 5 vegetative patients, with delayed latency in MCS and VS compared to healthy volunteers, indicating partially preserved semantic processing that is not necessarily conscious and cannot distinguish VS from MCS.

Abstract

<h3>Background</h3> A major challenge in the management of severely brain-injured patients with altered states of consciousness is to estimate their residual perception of the environment. <h3>Objective</h3> To investigate the integrity of detection of one's own name in patients in a behaviorally well-documented vegetative state (VS), patients in a minimally conscious state (MCS), and patients with locked-in syndrome. <h3>Design</h3> We recorded the auditory evoked potentials to the patient's own name and to 7 other equiprobable first names in 15 brain-damaged patients. <h3>Results</h3> A P3 component was observed in response to the patient's name in all patients with locked-in syndrome, in all MCS patients, and in 3 of 5 patients in a VS. P3 latency was significantly (<i>P</i>&lt;.05) delayed for MCS and VS patients compared with healthy volunteers. <h3>Conclusions</h3> These results suggest that partially preserved semantic processing could be observed in noncommunicative brain-damaged patients, notably for the detection of salient stimuli, such as the subject's own name. This function seems delayed in MCS and (if present) in VS patients. More important, a P3 response does not necessarily reflect conscious perception and cannot be used to differentiate VS from MCS patients.