 21. Emotion and Personality  467
granularity is often calculated separately for 
positive and negative emotions, as most peo -
ple strongly distinguish between these two 
broad categories of experience.
Emotional granularity has been of par -
ticular interest to clinical psychologists who 
study mental health and well-being. Low 
granularity, especially for negative emotion 
experience, has been linked consistently 
to disorders including depression, schizo -
phrenia, borderline personality disorder, 
and autism, among others, suggesting that 
the language-  based capacity to differenti -
ate between the varieties of emotion at the 
conceptual level is important to well-being 
(Smidt & Suvak, 2015). Low negative emo -
tion granularity is also associated with 
higher neuroticism and low self-  esteem, 
which has intriguing implications for under -
standing why high-  neuroticism individuals 
experience more intense and chronic nega -
tive affect (Erbas, Ceulemans, Pe, Koval, 
& Kuppens, 2014). A number of studies 
suggest that heightened negative emotion 
granularity is an asset for effective coping. 
High-  granularity individuals report using 
more diverse emotion regulation strategies 
over time, suggesting adaptive use of a cop -
ing “toolkit” rather than inflexible use of 
the same strategy regardless of the situation 
(Barrett, Gross, Christensen, & Benvenuto, 
2001). In a daily diary study, those with high -
er negative emotion granularity reported less 
aggressive behavior on days when they felt 
anger (Pond et al., 2012). Yet another study 
indicated that those high on negative emo -
tion granularity were less likely to consume 
alcohol when distressed, again suggesting 
reliance on healthier approaches to coping 
(Kashdan, Ferssizidis, Collins, & Muraven, 
2010). At least one study has suggested that 
higher positive emotion granularity is also 
associated with healthier emotion regulation 
(Tugade, Fredrickson, & Barrett, 2004).
The evidence so far provides preliminary 
support for emotional granularity as an im -
portant aspect of individual differences in 
emotion. However, many questions about 
granularity have yet to be addressed in de -
tail. What mechanisms produce individual 
differences in the granularity of experi -
ence? Is granularity purely a function of dif -
ferentiated conceptual knowledge around 
emotions, as suggested by Barrett and col -leagues (2001)? Or do more fine-  grained ap -
praisal, physiological, and/or interoceptive 
mechanisms lead to “real” differences in the 
specificity of emotional responding to differ -
ent kinds of events? What other aspects of 
personality and individual differences shape 
and are shaped by positive and negative 
emotion granularity? These and many other 
questions await future research.
Another new focus is on the dynamics of 
emotional experience . As we saw earlier, 
most studies linking emotion to personality 
have emphasized individual differences in 
the frequency and/or mean intensity of posi -
tive and negative affect. Yet emotions change 
over time, and these patterns of change dif -
fer from person to person (Eid & Diener, 
1999). Research on this phenomenon was 
pioneered by Peter Kuppens and colleagues, 
who have quantified several aspects of emo -
tional dynamics and linked these to aspects 
of personality and psychopathology. One 
approach examines the dynamics of positive 
and negative affect separately, calculating 
three aspects of within-  person change over 
time (Houben, Van Den Noortgate, & Kup -
pens, 2015): emotional variability,  the stan -
dard deviation or variance of affect intensity 
ratings over some time period; emotional 
instability,  or the extent of change in inten -
sity from one moment to the next (e.g., mean 
squared successive difference); and emotion -
al inertia,  the extent to which one is likely 
to remain “stuck” in an emotion state (e.g., 
high autocorrelation over time in NA inten -
sity). Additional measures capture change 
over time in the quality of affect rather than 
its intensity. For example, spin  is defined as 
the extent of change over time in the angles 
of vectors in two-  dimensional core affect 
space, like the hands of a clock, regardless 
of the intensity of the ratings (Kuppens, Van 
Mechelen, Nezlek, Dossche, & Timmer -
mans, 2007).
Results of a meta-  analysis indicate that 
high levels of emotional variability, instabil -
ity, and inertia predict risk of psychological 
disorders involving emotional symptoms, in -
cluding depression, bipolar disorder/mania, 
anxiety, borderline personality disorder, 
and externalizing disorders (Houben et al., 
2015). Effect sizes were considerably stron -
ger for negative emotion variability, instabil -
ity, and inertia than for positive emotion, 