Fig. 3

Results of the auditory oddball test. a Neural responses reflecting normal auditory function in the CLIS patient. Red bold and black dotted lines represent ERPs by deviant (240 trials) and standard (240 trials randomly selected from 600 trials) stimuli, respectively. The shaded area indicates the significant area as the result of the paired t-test between deviant and standard stimuli (p-value < 0.05). b Neural responses reflecting normal cognitive processes in the CLIS patient. Blue and red lines indicate ERPs by target (120 trials) and non-target (120 trials) stimuli, respectively. The shaded area indicates the significant area as the result of the paired t-test between target and non-target stimuli (p-value < 0.05). c An example of ERP waveforms obtained from a healthy subject after applying the same auditory oddball protocol used for the CLIS patient. The shaded area indicates the significant area as the result of the paired t-test between target and non-target stimuli (p-value < 0.05). d Neural responses showing abnormal cognitive decline after the CLIS patient’s physical status worsened. This result was obtained 4 months after the online experiment. We were unable to detect any evidence of consciousness or alertness of the patient