Implicit knowledge has been proposed to be the substrate of intuition because intuitive judgments resemble implicit processes. We investigated whether the automatically elicited mismatch negativity (MMN) component of the auditory event-related potentials (ERPs) can reflect implicit knowledge and whether this knowledge can be utilized for intuitive sound discrimination. We also determined the sensitivity of the attention-and task-dependent P3 component to intuitive versus explicit knowledge. We recorded the ERPs elicited in an "abstract" oddball paradigm. Tone pairs roving over different frequencies but with a constant ascending inter-pair interval, were presented as frequent standard events. The standards were occasionally replaced by deviating, descending tone pairs. The ERPs were recorded under both ignore and attend conditions. Subjects were interviewed and classified on the basis of whether or not they could datect the deviants. The deviants elicited an MMN even in subjects who subsequent to the MMN recording did not express awareness of the deviants. This suggests that these subjects possessed implicit knowledge of the sound-sequence structure. Some of these subjects learned, in an associative training session, to detect the deviants intuitively, that is, they could detect the deviants but did not give a correct description of how the deviants differed from the standards. Intuitive deviant detection was not accompanied by P3 elicitation whereas subjects who developed explicit knowledge of the sound sequence during the training did show a P3 to the detected deviants.

An EEG-compatible adaptation of the Trier Social Stress Test was developed to induce psychosocial stress in healthy subjects while investigating their auditory processing of unattended sounds and salivary levels of the stress hormone cortisol. The mismatch negativity (MMN) and N1/P2 were assessed using a multifeature paradigm, while subjects were attending to visual tasks with high or low attentional workload. Only the responses to duration change were affected by the stress manipulation. Cortisol levels during stress were inversely related to the MMN amplitudes of duration deviants. During anticipatory stress, responses to the standard tones (general sound processing) increased, but their amplitude was not correlated with cortisol levels. We found that psychosocial stressor anticipation attenuates both general and deviance-specific sound processing, suggesting that cortisol interferes with cortical memory-trace formation.

Most musicians express a close relationship with their musical instrument. Some even consider their instrument as a part of themselves, this type of relationship being anecdotally considered an advantageous one. A questionnaire survey on this relevant topic was conducted among 320 musicians. The musicians chose between one of the 4 proposed relationship types and completed questionnaires related to factors such as musical background, health aspects, mental distress symptoms, social phobia, music performance anxiety, and coping. The authors' results confirmed that feeling united with one's instrument is an advantageous relationship. Furthermore, they showed that there are further differences in aspects of professional well-being between musicians who identified themselves differently with their musical instrument. This musician-instrument relationship can, therefore, be considered a candidate index for professional well-being in musicians.

Music performance anxiety (MPA) is considered non-beneficial but its debilitating aspects are not directly addressed in current questionnaires ("general MPA"). Together with general MPA, we assessed "debilitating MPA" with questions about aspects that debilitate musical performance. In addition, since musicians often experience a beneficial aspect of MPA in the form of a performance boost, we assessed this boost with additional questionnaire items. The first goal of our questionnaire survey was to investigate whether general MPA is perceived as part of the same continuum as performance boost. Our second goal was to determine which aspects of MPA may lead to a downward spiral of a musical career. The results of our questionnaire survey of 320 professional and student musicians show that general MPA does not lie at the other end of the spectrum of boost. Instead, debilitating MPA with a weak career impact was influenced by boost and performance confidence. Debilitating MPA with a strong career impact was influenced by health and mental distress. Debilitating and general MPA were related to perceived pressure, whereas boost was related to perceived support. Perceived pressure and support might be more accessible anchor points in the treatment of MPA, and in the maintenance of a stimulating level of boost.