introduction
To understand exactly the relationship between alertness (arousal) and performance anxiety, it is first worth defining the two concepts separately. According to Dianna Kenny (2010):
music performance anxiety (MPA)
is the experience of marked and persistent anxious apprehension related to musical performance. It has arisen through underlying biological and/or psychological vulnerabilities and/or specific anxiety-conditioning experiences. It is manifested through combinations of affective, cognitive, somatic, and behavioral symptoms. It may occur in a range of performance settings, but is usually more severe in settings involving high ego investment, evaluative threat and fear of failure.
Both the literature and the practice indicate that the musicians experience the highest levels of music performance anxiety in the situation of the audition (during studies: in exam situation). An orchestral or vocal audition is both a performance and a stressful job interview. The situation is often unpredictable, there is not much you can control (re-scheduling, delays, interruptions by the jury, comments or complete lack of feedback) and the competition – and therefore the possibility of failure – is very high.
On top of that,
MPA may be focal (i.e. focused only on music performance), or occur comorbidly with other anxiety disorders, in particular social phobia. It may or may not impair the quality of the musical performance. It affects musicians across the lifespan and is at least partially independent of years of training, practice, and level of musical accomplishment.
Arousal
is the level of excitement in our nervous system. Lower arousal typically means a calm, relaxed state, but can also mean a state that is drowsy and lethargic. In contrast, high levels of arousal can make us feel “on the go”, energetic, focused and ready for action, but can also cause anger and anxiety. As defined by Gould & Udry (1994):
arousal is a general physiological and psychological activation of the organism that varies on a continuum from deep sleep to intense excitement.
Adequate arousal levels are essential for optimal performance. But what is adequate? This is a question that many researchers have tried to answer over the last 120 years.
yerkes-dodson law
The inverted U-shaped curve of the Yerkes-Dodson law shows that a medium level of arousal leads to the best performance, while too low or too high a level leads to poor performance.
However, already in the original research, two different rules were defined, depending on how difficult the task was.
For easy tasks there is a linear relationship between performance and arousal. It is for more complex tasks (like a music performance of a relatively difficult piece) where too high level of arousal can have a negative effect.


reversal theory
Apter found this theory too simplistic, as it only dealt with the level of arousal, but not its quality. In his reversal theory, he distinguishes between an extra dimension: pleasantly and unpleasantly high arousal and pleasantly and unpleasantly low arousal.
The term “reversal” means that, depending on the situation, we can also vary between a high or low level of arousal, depending on which is optimal in the given moment.

individual zone of optimal functioning
Most would agree that in a pleasantly relaxed, calm state it might be difficult to perform a pole vault or to sing Queen of the Night – but some people like excitement more than others. IZOF theory is based on the observation that higher arousal levels can have a stimulating as well as inhibitory effect and takes into account differences between individuals.
Setting the IZOF for a musician or athlete means defining the optimal physical and mental state in which that person can perform their best – and providing them with the tools to raise or lower their own arousal levels before a sports competition or concert if needed.

complex performance model
(Wilson 1994; Williams & Krane, 2021)
The basic idea was taken forward by Wilson. His three-dimensional model of anxiety related to sports or music performance is based on (1) task mastery, (2) trait anxiety and (3) state anxiety.
Williams and Krane (2021) point to a possible fourth modulating factor, which is introversion/extroversion.

the catastrophe theory
According to the peak catastrophe theory, a steady increase in the level of one of the factors leads to a sudden deterioration in performance after reaching the “peak”, i.e. the highest possible value. During musical or athletic performance, the critical coincidence typically occurs between the level of physiological arousal and the level of cognitive anxiety (such as intrusive negative thoughts regarding own performance or the possible evaluation).

Modern performance psychology is mostly based on the complex model presented in the book by Williams & Krane, but many opera singers and instrumental musicians feel that the catastrophe model is the closest to their reality (think of the circumstances under which a high note most often cracks).
It is definitely worthwhile (with the help of a professional, for example) to assess your own optimal zone of functioning and learn techniques to increase and decrease arousal. This approach takes into account individual characteristics, personality traits and preferences, so any intervention is guaranteed to be personalised.
sources
Apter, M. J. (1984). Reversal theory and personality: A review. Journal of Research in Personality, 18(3), 265–288. https://doi.org/10.1016/0092-6566(84)90013-8
Gould, D., & Udry, E. (1994). Psychological skills for enhancing performance: arousal regulation strategies. Medicine & Science in Sports & Exercise, 26(4), 478–485.
Hanin, Y. L. (2000). Individual Zones of Optimal Functioning (IZOF) Model: Emotion-performance relationship in sport. Emotions in sport. (65–89). Human Kinetics.
Hardy, L., & Parfitt, G. (1991). A catastrophe model of anxiety and performance. British Journal of Psychology, 82(2), 163–178. https://doi.org/10.1111/j.2044-8295.1991.tb02391.x
Kenny, D. T. (2010). Negative emotions in music making: Performance anxiety. W P. Juslin & J. Sloboda (ed.), Handbook of Music and Emotion: Theory, Research, Applications. Oxford University Press.
Williams, J. M., & Krane, V. (2021). Applied sport psychology : personal growth to peak performance (8th edition). McGraw Hill Education.
Wilson, G. D. (1994). Psychology for performing artists : butterflies and bouquets. J. Kingsley Publishers.
Woytynowska, K. A. (2024). Applying sports psychology techniques to classical musicians and opera singers: the effect of intervention on levels of psychological coping skills, music performance anxiety, situational anxiety and situational self-confidence. MA thesis. Wyższa Szkoła Biznesu – National Louis University
Yerkes, R. M., & Dodson, J. D. (1908). The relation of strength of stimulus to rapidity of habit-formation. Journal of Comparative Neurology and Psychology, 18(5), 459–482
