Psychophysiological correlates of coping and quality of life in patients with ALS.

OBJECTIVE: Self-regulation models of coping suggest that patients with chronic diseases reporting low quality of life (QoL), an indicator of failed coping efforts, should show facilitated access to disease related words. Here we investigated whether a reduced N400 amplitude within an incongruent, i.e. unpredictable disease-related context would be a correlate of this facilitated access. METHODS: ERPs were recorded in N=18 patients with amyotrophic lateral sclerosis (ALS) and N=20 age-matched healthy controls during reading of sentences, ending either with congruent or incongruent words. Incongruent and congruent words were disease related or disease unrelated. Mean N400 amplitudes were analyzed with mixed models. RESULTS: Generally, incongruent words elicited a more negative N400 amplitude than congruent words in all groups and conditions, i.e. an N400 effect. In patients with high QoL this N400 effect did not differ between disease related and unrelated words. In patients with low QoL, however, the N400 effect was significantly smaller for disease related than for disease unrelated words. In healthy controls N400 amplitudes showed no such interaction between congruence, disease relatedness and QoL. Results remained stable when controlling for disease severity, duration and depression. CONCLUSION: The N400 indicates increased accessibility to disease related information in ALS patients with low QoL. The increased access may imply a constantly activated disease related context which is linked to low QoL. SIGNIFICANCE: N400 modulation by disease related information may serve as a psychophysiological correlate of coping and the patient's QoL.

The auditory p300-based SSBCI: a door to minimally conscious patients?

In this study we report on the evaluation of a novel auditory single-switch BCI in nine patients diagnosed with MCS. The task included a simple and a complex oddball paradigm, the latter uses the tone stream segregation phenomenon. In all patients a significant difference between deviant and frequent tones could be observed in EEG. However, in some cases the deviant tones produce a significant negative peak and in some a very late positive peak. These preliminary findings are relevant in order to address future customization of this auditory ssBCI-based paradigm for unresponsive patients.