TY - JOUR A1 - Erlbeck, Helena A1 - Kübler, Andrea A1 - Kotchoubey, Boris A1 - Veser, Sandra T1 - Task instructions modulate the attentional mode affecting the auditory MMN and the semantic N400 JF - Frontiers in Human Neuroscience N2 - Event-related potentials (ERPs) have been proven to be a useful tool to complement clinical assessment and to detect residual cognitive functions in patients with disorders of consciousness. These ERPs are of ten recorded using passive or unspecific instructions. Patient data obtained this way are then compared to data from healthy participants, which are usually recorded using active instructions. The present study investigates the effect of attentive modulations and particularly the effect of activevs. passive instruction on the ERP components mismatch negativity (MMN) and N400. A sample of 18 healthy participants listened to three auditory paradigms: anoddball, aword priming, and a sentence paradigm. Each paradigm was presented three times with different instructions: ignoring auditory stimuli, passive listening, and focused attention on the auditory stimuli. After each task, the participants indicated their subjective effort. The N400 decreased from the focused task to the passive task, and was extinct in the ignore task. The MMN exhibited higher amplitudes in the focused and passive task compared to the ignore task. The data indicate an effect of attention on the supratemporal component of the MMN. Subjective effort was equally high in the passive and focused tasks but reduced in the ignore task. We conclude that passive listening during EEG recording is stressful and attenuates ERPs, which renders the interpretation of the results obtained in such conditions difficult. KW - ERP KW - priming KW - selective attention KW - event-related potentials KW - vigilance decrement KW - brain potentials KW - vegetative state KW - consciousness KW - component KW - predicts recovery KW - mismatch negativity KW - attention KW - instruction KW - N400 KW - MMN Y1 - 2014 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-115553 VL - 8 IS - 654 ER - TY - JOUR A1 - Cheetham, Marcus A1 - Wu, Lingdan A1 - Pauli, Paul A1 - Jancke, Lutz T1 - Arousal, valence, and the uncanny valley: psychophysiological and self-report findings JF - Frontiers in Psychology N2 - The main prediction of the Uncanny Valley Hypothesis (UVH) is that observation of humanlike characters that are difficult to distinguish from the human counterpart will evoke a state of negative affect. Well-established electrophysiological [late positive potential (LPP) and facial electromyography (EMG)] and self-report [Self-Assessment Manikin (SAM)] indices of valence and arousal, i.e., the primary orthogonal dimensions of affective experience, were used to test this prediction by examining affective experience in response to categorically ambiguous compared with unambiguous avatar and human faces (N = 30). LPP and EMG provided direct psychophysiological indices of affective state during passive observation and the SAM provided self-reported indices of affective state during explicit cognitive evaluation of static facial stimuli. The faces were drawn from well-controlled morph continua representing the UVH' dimension of human likeness (DHL). The results provide no support for the notion that category ambiguity along the DHL is specifically associated with enhanced experience of negative affect. On the contrary, the LPP and SAM-based measures of arousal and valence indicated a general increase in negative affective state (i.e., enhanced arousal and negative valence) with greater morph distance from the human end of the DHL. A second sample (N = 30) produced the same finding, using an ad hoc self-rating scale of feelings of familiarity, i.e., an oft-used measure of affective experience along the UVH' familiarity dimension. In conclusion, this multi-method approach using well-validated psychophysiological and self-rating indices of arousal and valence rejects for passive observation and for explicit affective evaluation of static faces the main prediction of the UVH. KW - emotional facial expressions KW - event-related potentials KW - electromyographic activity KW - startle reflex KW - arousal KW - unpleasant pictures KW - brain potentials KW - mere exposure KW - circumplex model KW - face recognition KW - neural response KW - valence KW - uncanny valley hypothesis KW - familiarity KW - EMG KW - EEG KW - LPP Y1 - 2015 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-151519 VL - 6 IS - 981 ER -