Abstract: Affect spin reflects the time-fluctuation characteristics of the individual. As non-cognitive personality that measures the intraindividual variability of core affect, affect spin is important for us to understand the individual difference in affect intravariability over time and its mental functions. Relative to affect flux, affect pulse, and other affect variability indicators within the individual, the main advantage of affect spin is that it constructs the position change trajectory in core affect space by using the method independent of reference dimension and experience intensity. And it focuses on temporal characteristics of the naturally occurring core affect state, rather than relies on a certain type of core affect dimension characteristics to explain affect variability.
For the measurement, experience sampling method and day reconstruction method are generally adopted, and individuals assess their affect state in the present situation (or recall it) by constructing Affect Grid or performing adjective rating. The acquisition process and conversion method are relatively complicated in that people need to repeatedly track their daily core affect state, and affect spin can be representative as cross-time standard deviation of the vector angle of individual core affect space position within the evaluation period.
Affect spin is thought to play a central role in the mental health such that having stable affect would strengthen people's sense of security and control, thereby enhancing the level of adjustment of their mental health. Instead, when people always change their affects, it is difficult for them to anticipate their lives, and might generate self-conflict. As a result, they may lower their expectations for the future, and furthermore weaken mental health. Based on Affective Events Theory and Dynamics Model of Affect, we suggest that the experience of negative-inducing events and its assessments lead to the individual affect spin, and psychological adjustment, psychological disorders, problem behaviors, etc. are the consequences of affect spin. However, some qualities of mental health, such as interpersonal relationship, are difficult to determine whether it is the cause or the result of affect spin. It is more likely that there is a bidirectional relationship between them. In short, the occurrence and development of affect spin reflect the nature of the process of affect's temporal dynamic variability on individuals' physical and mental health, that is, the most fundamental reason that affect spin influences mental health lies in the affect destruction caused by negative events in life.
However, the current empirical research about the effect of affect spin on mental health is still very limited. In the future, it is highly suggested to explore the process mechanism of affect spin on mental health. Attention should also be paid to investigate the joint mechanism of affect variability and its stability indicators on mental health function. At the same time, it should be strengthened to examine the influencing process of state affect spin on the individual's mental health function, especially the dynamic relationship mechanism with the stability of interpersonal relationship.

Key words: affect spin, core affect, intraindividual variability, measurement method, mental health