CHAPTER 25 Depression in Early Childhood Joan L. Luby Diana Whalen Only in the last 10 years have the mental health rized that several core emotions are present at and developmental communities generally ac- birth in the human infant. Subsequently, em- cepted that depression may arise in very early pirical studies provided support for this hypoth- childhood. As early as the 1940s, clinical de- esis (e.g., Izard, Huebner, Risser, & Dougherty, pression was observed and described in infants 1980). Despite these early insights, a significant deprived of primary caregiving relationships body of empirical data that began to outline the (Spitz, 1946). However, in subsequent years, trajectory of early emotion development did not prevailing developmental theory suggested that become available until the late 1980s. Over the young children are too immature to experience last two decades, data informing how children the core emotions of depression, thereby ruling recognize and express discrete emotions, devel- out the possibility of clinical depression before op the ability to regulate emotional responses, school age (Rie, 1966). Subsequent advances in understand the causes and consequences of studies of early childhood emotion development emotions, as well as experience more complex provided data refuting this claim, demonstrat- emotions, have become available (for review, ing the previously unrecognized emotional so- see Denham, 1998; Saarni, 1999). While these phistication of infants and toddlers (Denham, data have provided a broad framework illustrat- 1998; Shonkoff & Phillips, 2000). Despite this, ing that emotional competence develops earlier empirical data to validate and describe a clini- in life than previously recognized, many details cal depressive syndrome in infants and toddlers about when and how emotional development under the age of 3 years remains scarce, with unfolds in the infancy and preschool period re- some retrospective data suggesting it may arise main understudied. Further investigation of this in the toddler years (Luby & Belden, 2012). early trajectory may be key to understanding In order to understand whether depression the earliest possible onset of depression and its can arise early in life and how it might mani- developmental characteristics. fest, it is essential to understand the norma- From a public health perspective, the identifi- tive trajectory of early emotional development. cation of depression at the earliest possible point Normative emotional development provides a in development is an important goal because not framework against which alterations in early only is relieving the suffering of young children emotional experiences and expressions can be a necessary and worthy cause, but also earlier assessed. In the late 1800s, based on observa- intervention may provide a window of opportu- Copyright @ 2019. The Guilford Press. All rights reserved. May not be reproduced in any form without permission from the publisher, except fair uses permitted under U.S. or applicable copyright law. tion of facial expressions, Darwin (1872) theo- nity for greater therapeutic change and benefit. 426 EBSCO : eBook Collection (EBSCOhost) - printed on 7/2/2019 3:14 PM via TUFTS UNIV AN: 1843598 ; Zeanah, Charles H..; Handbook of Infant Mental Health, Fourth Edition Account: s3579704.main.ehost 25. Depression in Early Childhood 427 The unique efficacy of early intervention dur- ed. This suggests that impairments or altera- ing the preschool period has been demonstrated tions in this domain are likely to be associated for several specific childhood mental disorders with early-onset mood disorders and should such as autistic spectrum disorder and some therefore be explored. disruptive disorders (e.g., Eyberg et al., 2001; Charles Darwin was the first to suggest that Faja & Dawson, 2006; Webster-Stratton, Reid, human infants are born with the ability to ex- & Beauchaine, 2013). This may be related to press a limited repertoire of discrete emotions. greater neuroplasticity and therefore increased Subsequently, developmental psychologist Car- sensitivity to environmental inputs earlier in roll Izard and colleagues (1980) provided em- development (Troller-Renfree & Fox, 2016). pirical data demonstrating that human infants Early intervention may be of particular impor- displayed specific and discrete facial expres- tance in depressive disorders given the known sions that were consistent with incentive events chronic and relapsing course, suboptimal treat- designed to evoke these emotional states. Per- ment responses, and high rates of treatment re- tinent to the development of depression in in- sistance in older depressed children and adoles- fancy is the normative development of sadness cents (Kennard et al., 2006; Weisz, McCarty, & and joy. Izard, Hembree, and Huebner (1987) Valeri, 2006). For these reasons, as well as the showed that facial expressions of sadness can compelling accounts of clinical observation of be clearly and reliably distinguished from other depressive affect very early in life, depression is negative emotions by the age of 2 months in a disorder for which the earliest possible identi- human infants. Furthermore, by age 6 months, fication may hold promise to advance the public sad facial expression arise in response to or con- health; therefore, early identification is impera- current with sadness-provoking incentive events tive and early interventions are necessary. (Izard et al., 1995). Similarly, studies have also We explore in this chapter the empirical and shown that human infants display discrete fa- theoretical literature on depression in infants, cial expressions of joy as early as 6–8 months toddlers, and preschool-age children. We begin of life. The greater differentiation of emotional the discussion with the preschool period, which expression in which more subtle and complex has the largest body of available empirical data. expressions are observed occurs after the first Then, we explore the relevant literature and year of life (Demos, 1986). These findings that available data pertaining to toddlers and in- demonstrate the experiences of sadness and joy fants. In these youngest age groups, there is a appear to arise in human infants during the first much smaller body of available empirical data 6 months of life suggest that depressive affects on clinical symptoms or syndromes. However, also may be possible at this early stage of devel- we do review related literature on early altera- opment. However, as outlined below, apart from tions in emotion expression and neural func- compelling clinical observations, there are no tioning in high-risk groups, and discuss novel empirical data to address the issue of whether early interventions for depression that are cur- depression arises in infancy. rently being tested. Emotional expression of joy and sadness, as well as emotion recognition of these emotions and more complex emotions such as guilt, has Emotion Development in Early-Onset Depression received more empirical attention in older pre- school children for obvious reasons. One area of A developmental issue of interest in the study of interest is whether depressed preschoolers may early-onset depression, as well as mood disor- demonstrate an earlier ability to recognize and ders more generally, is the question of whether label negative emotions compared to nonde- early alterations in patterns of emotion devel- pressed preschoolers. There is some support for opment can be identified. This is important the notion that early experiences of depression not only for the purpose of identifying devel- may enhance the ability to recognize and label opmental manifestations of early-onset mood negative emotions, specifically sadness (Han- disorders, but also, and perhaps more clinically kin, Gibb, Abela, & Flory, 2010; Lopez-Duran, relevant, to specify developmental targets for Kuhlman, George, & Kovacs, 2013). Further fo- early intervention. Recognizing that emotional cused investigations of clinically relevant alter- competence develops earlier than previously ations in emotion development are now needed. thought and develops rapidly during infancy An investigation of the development of Copyright @ 2019. The Guilford Press. All rights reserved. May not be reproduced in any form without permission from the publisher, except fair uses permitted under U.S. or applicable copyright law. and preschool years has been clearly document- more complex emotions, particularly guilt and EBSCO : eBook Collection (EBSCOhost) - printed on 7/2/2019 3:14 PM via TUFTS UNIV AN: 1843598 ; Zeanah, Charles H..; Handbook of Infant Mental Health, Fourth Edition Account: s3579704.main.ehost 428 IV. Psychopathology shame, are of special interest given the central clitic depression,” and he speculated that it was importance of these emotions to depressive based on the infant’s reaction to separation from states. Kochanska, Gross, Lin, and Nichols a primary caregiver. Underscoring the life-sus- (2002) have previously shown that children un- taining importance of the emotional elements derstand the experience of guilt as early as 3 of the early caregiving relationship, these in- years of age. In light of this finding, we hypoth- fants deprived of primary caregivers displayed esized that depressed preschoolers, like older failure to thrive, despite adequate nutrition and depressed individuals, would experience higher physical care. Despite this compelling finding levels of guilt than nondepressed preschoolers. of depressed affect