title: Intrinsic Emotional Fluctuation in Daily Negative Affect across Adulthood.
abstract: The study explored daily negative affect (NA) fluctuation, its associations with age, and its developmental characteristics.
  
  
  
  The sample (n = 790) was drawn from the Midlife Development in the United States; participants completed two 8-day daily diaries 10 years apart. Multilevel models were estimated within each diary component, where two single daily NA (depression and nervousness) and daily NA diversity were predicted separately by daily stressor exposures, physical health symptoms, age, gender, education, and neuroticism. The variances of within-person residual were output for single NA and NA diversity as intrinsic emotion fluctuation (IEF) within each diary component (i.e., controlled for within- and between-person contextual factors). Then multilevel growth models were fit to explore the developmental characteristics of day-to-day IEF across 10 years.
  
  
  
  At the daily level, older age was associated with less IEF in depression and nervousness. Over time, IEF in depression decreased. Additionally, IEF in NA diversity increased for older participants longitudinally.
  
  
  
  IEF represents a new conceptualization of midlife individuals' daily emotional ups and downs, specifically, the intrinsic within-person volatility of emotions. The magnitude of IEF and its longitudinal dynamics may have implications for health and well-being of middle-aged adults.
authors.affiliation: Center for Healthy Aging, The Pennsylvania State University, State College.
authors.forename: Yin
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Robert D. and Patricia E. Kern Center for the Science of Healthcare Delivery, Care Experiences Program, Mayo Clinic, Rochester, Minnesota.
authors.forename: Lauren R
authors.initials: LR
authors.lastname: Bangerter
authors.affiliation: Human Development and Quantitative Methods Division, Graduate School of Education, University of Pennsylvania, Philadelphia.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Rovine
authors.affiliation: Department of Human Development and Family Studies, The Pennsylvania State University, State College.
authors.forename: Steven H
authors.initials: SH
authors.lastname: Zarit
authors.affiliation: Center for Healthy Aging, The Pennsylvania State University, State College.|Department of Human Development and Family Studies, The Pennsylvania State University, State College.
authors.forename: David M
authors.initials: DM
authors.lastname: Almeida
mesh_terms: D000203:Activities of Daily Living / Q000523:psychology*; D000328:Adult; D000339:Affect; D000367:Age Factors; D000368:Aged; D004644:Emotions; D005260:Female; D006801:Humans; D007206:Individuality; D008297:Male; D008875:Middle Aged; D055815:Young Adult
keywords: Growth curve; Intrinsic emotion fluctuation; Midlife; Multilevel heterogeneous model; Negative affect