Pediatric Annals

Special Issue Article 

Developmental Aspects of Pediatric Mental Health

Rachel Ballard, MD; Marisa Perez-Reisler, MD


Mental health disorders emerge in predictable patterns across pediatric development. Understanding these patterns can help clinicians anticipate emerging mental health problems. In this article, we review child development, merging concepts from developmental psychology with motor, language, cognitive, and social development. We point out developmental red flags for mental health disorders in each developmental period. [Pediatr Ann. 2020;49(10):e426–e430.]


Mental health disorders emerge in predictable patterns across pediatric development. Understanding these patterns can help clinicians anticipate emerging mental health problems. In this article, we review child development, merging concepts from developmental psychology with motor, language, cognitive, and social development. We point out developmental red flags for mental health disorders in each developmental period. [Pediatr Ann. 2020;49(10):e426–e430.]

Pediatric medicine is rooted in a developmental framework that informs differential diagnosis and treatment planning. Anticipatory guidance, a hallmark of pediatric well childcare, relies on an understanding of child growth and development, and underlies risk reduction strategies and targeted screening.

Mental health disorders emerge in predictable patterns across pediatric development. Understanding these patterns can help clinicians anticipate emerging mental health concerns. In this article, we review child development and point out developmental red flags for mental health disorders in each developmental period.

All pediatric mental health disorders have multifactorial etiologies with genetics, life history, and environmental factors contributing to risk. The developmental model presented here does not indicate the etiology of all mental health conditions and will not predict every case. We cover only the more common mental health disorders of childhood and adolescence. Developmental stages and corresponding periods of mental health risk are summarized in Figure 1.

Developmental periods and age of onset risk of common disorders of child and adolescent mental health.

Figure 1.

Developmental periods and age of onset risk of common disorders of child and adolescent mental health.

Infancy: 0–12 Months

A major task of infancy is the formation of attachment to a person, usually a parent, who is charged with meeting the infant's needs. Parents differ in the skill and consistency with which they meet those needs; greater skill and consistency is associated with more secure infant attachment. Infant emotional development is dyadic, occurring in relationship with a parent who interacts reciprocally, responding to the infant's sounds, movements, and expressions. Through reciprocal interactions, the infant learns the first steps of self-regulation. Motor skills develop from purposeless movement to intentional reaching and grasping. Cognitive skills, including the concept of object permanence, emerge as the infant looks for a toy.

Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by problems with social relatedness, repetitive or restrictive behaviors, and difficulties with pragmatic language. Autism symptoms may be seen in infancy, with motor and sensory concerns appearing as early as age 6 months. Social communication and repetitive behavior concerns in ASD emerge in the second and third years of life.1 Despite limited social relatedness, children with ASD form attachments similarly to typically developing children.2

Toddlerhood and Preschool: 13–60 Months

Walking, and then running, grant the toddler the capacity to wander from their parent, explore the world, and return to the parent when stressed or afraid. Preschool-age children learn tasks that give them autonomy, such as dressing themselves, toileting, and playing independently. Preschool-age children express emotions using language rather than behaviorally. Cognitively, the preschool-age child begins to think in categories, understand cause and effect, and anticipate consequences of behavior. They begin to experience guilt and have an initial understanding of right and wrong.

Self-regulation is the capacity to bring oneself back to an even keel emotionally after or during an experience of discomfort, frustration, or fear. The infant learns self-regulation in the dyad; the parent helps bring the crying infant to a state of calm. In the toddler and preschool years, self-regulation still involves the parent, but is increasingly under control of the child. This does not happen evenly or easily in all children; tantrums typically peak around age 2 years and gradually decrease. Disorders of mental health, which most commonly emerge in the preschool years, are to some extent disorders of self-regulation.

Children with oppositional defiant disorder (ODD) argue, tantrum, and refuse requests to perform non-preferred tasks. Children with a more negative, irritable, or dysphoric temperament are more likely to develop ODD. They engage in these behaviors during the developmental stage when their peers are learning problem-solving skills and developing frustration tolerance. Delays in expressive language development or in the cognitive development of inhibitory control (being able to inhibit an initial response like grabbing and substitute a secondary response like asking) are associated with ODD. ODD symptoms may be reinforced by the behavior of those around the child, as when parents yield to tantrum behavior and children learn that tantrums are effective tools.

Attention-deficit/hyperactivity disorder (ADHD) is a neurobehavioral disorder often recognized in the preschool years as a child is unable to pay attention or control his movement and impulses to the degree expected for his age. To some extent the child with ADHD has a maturational delay with impulse control, problem solving, and social skills lagging behind those of their peers. Imaging studies support the model of maturational lag in the brain's functional architecture in youth with ADHD.3 ADHD symptoms in turn may affect ongoing development and risk for later mental health comorbidities.4

Behavioral inhibition is a temperamental quality characterized by vigilance during novel or unfamiliar situations. Preschool-age children with behavioral inhibition avoid or withdraw from new people or situations and are at risk for social anxiety disorder later in adolescence, particularly if they are also prone to focus on making errors when observed socially.5

School Age: 6–12 Years

The years of middle childhood are dominated by school and the shift to social life outside of the family. The school-age child develops logic and reasoning, time organization, sustained attention, and problem-solving skills. The child internalizes values and norms and develops a conscience. Rules and fairness become very important. They can observe and appraise themselves. Major developmental tasks involve mastery of skills and capacity for both competition and cooperation. The early school-age years are marked by magical thinking, which is gradually supplanted by logic and the ability to take the viewpoint of others.

Specific phobias are common in younger school-age children: magical thinking and growing awareness of the larger world can develop into fears of the dark, storms, dogs, or insects. Some children develop phobias around medical procedures such as immunizations, throat swabs, or pill swallowing. Specific phobias often co-occur with other anxiety disorders.

Early school-age children may struggle with the developmental transition to spending much of the day away from home and parents. Separation anxiety disorder arises when a child displays fear regarding potential or actual separations from their attachment figure, usually a parent. The child worries that bad things will happen to their parent if they are not with them, and resists separating from the parent for activities with others. They may complain of aches and pains to bring their parent back to them. Separation anxiety may be associated with school avoidance, lack of participation in developmentally normative activities, and other anxiety disorders in later childhood.6

Generalized anxiety disorder is the tendency to worry excessively and constantly about uncertainty, danger, or failure. Whereas peers are working on mastery, children with generalized anxiety disorder are overwhelmed by uncertainty and the possibility of failure and unsure of their capacity to meet developmentally appropriate challenges such as negotiating friendships and meeting real or perceived expectations. They predict disaster, failure, or danger around every corner. They may become tense, irritable, and exhausted.7

Adolescence: 13–18 Years

Adolescence is a period of transformation and increased autonomy. Adolescents are adapting to sexually maturing bodies. They are developing deductive reasoning and abstract thinking skills, more mature decision-making and problem-solving, yet often misperceiving risk or vulnerability. They are establishing key aspects of identity in their peer groups and society and identifying moral standards and beliefs. They are taking on increasingly mature roles and renegotiating relationships with parents and other adults.

The depressive disorders, major depression disorder (MDD) and dysthymia, are uncommon before adolescence. MDD occurs in less than 2% of prepubertal children, but becomes common in the teenage years, with a prevalence of 4% to 8% and cumulative incidence of 20% by age 18 years. MDD, like other mental health disorders, is multifactorial. Cognitive features in younger children, including difficulty shifting attention and switching activities, predict later onset of depression and anxiety.8 Parental depression is a major risk factor for adolescent depression in offspring.9 The timing of puberty is important; for example, when girls develop early and boys develop late; this may be an indicator of higher risk for depression.10

Typically developing adolescents struggle to define their identity and experience doubts about their appearance, tastes, and acceptance by peers. Teenagers with social anxiety disorder experience fear of social and performance settings to an extreme degree. They are reticent to speak in social situations and at school, negatively affecting their academic performance. They feel that they are constantly being judged and found lacking or are about to make a catastrophic social error. They may feel nauseous, flushed, or sweaty around others. Teenagers who are more socially anxious avoid the social challenges of adolescent life—there are fewer opportunities to establish identity and a sense of efficacy in academic, work, and recreational settings, resulting in increasing impairment over time.11

Trajectories toward substance use disorders begin with intrinsic child traits interacting with environmental factors over the developmental period. High-risk traits for later substance use disorders include thrill seeking and lack of fear combined with unwillingness to follow rules, accept adult supervision, and endorse ethical values. Contextual factors, including poor parent-child relationships, harsh and inconsistent discipline, and parental substance abuse in a setting of access to drugs through peer use, may lead to adolescent substance abuse.12

Conduct disorder is a pattern of behaviors that oppose social and legal norms. Childhood-onset conduct disorder is strongly associated with early onset ODD, ADHD, family dysfunction, and greater risk of violent behavior in young adulthood. However, many children with ADHD and oppositional behavior do not go on to develop conduct disorder, and treatment of both conditions may reduce risk of progression. Adolescent-onset conduct disorder is not associated with ADHD or family dysfunction.13

Bipolar disorder is characterized by at least one manic or hypomanic episode, generally involves cycles of manic and depressive episodes, and is quite rare prior to age 16 years. Children and younger adolescents with irritable mood, low frustration tolerance, and anger outbursts maybe considered to have bipolar disorder but this behavioral pattern is more likely associated with anxiety disorder prepubertally, irritable depression, ODD, or a trauma history. In many children, emotional reactivity and anger outbursts represent delayed or lagging skills in the areas of self-regulation, verbal expression of emotions, and problem solving.

The mean age of onset of schizophrenia is 15 to 30 years, with mean male onset about 2.5 years earlier than female. Developmental risk factors for schizophrenia include, among many, a family history of schizophrenia, pregnancy or obstetric complications, immigrant status, and childhood cognitive and motor differences. True schizophrenia before mid-adolescence is quite rare. However, the appearance of auditory or visual hallucinations in younger children is not uncommon and often related to anxiety, stress, and trauma. Children who have experienced trauma may report hallucinatory-like episodes of re-experiencing the traumatic event. Younger children may report conversations with or seeing imaginary friends, or images of their emerging consciences (angels and devils, monsters) as if they were real. Children with severe depression may experience auditory hallucinations, which echo their depressed thoughts. Fever, delirium, and underlying medical disorders should be considered in children with new-onset psychotic symptoms.14 Medications, including cough and cold medications, may be associated with visual hallucinations.

The Role of Trauma

Emotional, psychological, and cognitive developmental stages can be altered or delayed at any age as the result of traumatic events. Childhood trauma may include severe single-traumatic episodes and complex trauma (exposure to multiple traumatic events, often of an interpersonal nature such as abuse or severe neglect). Pre-existing conditions or risks (eg, anxiety and depressive disorders) predict persistence of trauma symptoms as do marked changes in posttrauma life status (eg, marked reduction in socio-economic status). Intensive or long-term medical care is increasingly recognized as a source of childhood trauma.15 A trauma-informed approach minimizes the potential for medical care to traumatize patients, families, and staff.16


Through anticipatory guidance, pediatric clinicians promote health, mitigate risk, and identify early signs of disorders or diseases. This is equally true for mental and physical health. Disorders of mental health, for the most part, arise in predictable ways at predictable stages of development. Being able to see what is coming allows clinicians to engage in proactive mental health partnerships with patients and families.


  1. Sacrey LA, Zwaigenbaum L, Bryson S, et al. Can parents' concerns predict autism spectrum disorder? A prospective study of high-risk siblings from 6 to 36 months of age. J Am Acad Child Adolesc Psychiatry. 2015;54(6):470–478. doi:10.1016/j.jaac.2015.03.014 [CrossRef] PMID:26004662
  2. McKenzie R, Dallos R. Autism and attachment difficulties: overlap of symptoms, implications and innovative solutions. Clin Child Psychol Psychiatry. 2017;22(4):632–648. doi:10.1177/1359104517707323 [CrossRef] PMID:28530116
  3. Sripada CS, Kessler D, Angstadt M. Lag in maturation of the brain's intrinsic functional architecture in attention-deficit/hyperactivity disorder. Proc Natl Acad Sci USA. 2014;111(39):14259–14264. doi:10.1073/pnas.1407787111 [CrossRef] PMID:25225387
  4. Humphreys KL, Galán CA, Tottenham N, Lee SS. Impaired social decision-making mediates the association between ADHD and social problems. J Abnorm Child Psychol. 2016;44(5):1023–1032. doi:10.1007/s10802-015-0095-7 [CrossRef] PMID:26486935
  5. Buzzell GA, Troller-Renfree SV, Barker TV, et al. A neurobehavioral mechanism linking behaviorally inhibited temperament and later adolescent social anxiety. J Am Acad Child Adolesc Psychiatry.2017;56(12):1097–1105. doi:10.1016/j.jaac.2017.10.007 [CrossRef] PMID:29173744
  6. Vaughan J, Coddington JA, Ahmed AH, Ertel M. Separation anxiety disorder in school-age children: what health care providers should know. J Pediatr Health Care. 2017;31(4):433–440. doi:10.1016/j.pedhc.2016.11.003 [CrossRef] PMID:28012800
  7. Dillon-Naftolin E. Identification and treatment of generalized anxiety disorder in children in primary care. Pediatr Ann. 2016;45(10):e349–e355. doi:10.3928/19382359-20160913-01 [CrossRef] PMID:27735970
  8. Mezulis A, Salk RH, Hyde JS, Priess-Groben HA, Simonson JL. Affective, biological, and cognitive predictors of depressive symptom trajectories in adolescence. J Abnorm Child Psychol. 2014;42(4):539–550. doi:10.1007/s10802-013-9812-2 [CrossRef] PMID:24158642
  9. Fischer AS, Camacho MC, Ho TC, Whitfield-Gabrieli S, Gotlib IH. Neural markers of resilience in adolescent females at familial risk for major depressive disorder. JAMA Psychiatry. 2018;75(5):493–502. doi:10.1001/jamapsychiatry.2017.4516 [CrossRef] PMID:29562053
  10. Galvao TF, Silva MT, Zimmermann IR, Souza KM, Martins SS, Pereira MG. Pubertal timing in girls and depression: a systematic review. J Affect Disord. 2014;155:13–19. doi:10.1016/j.jad.2013.10.034 [CrossRef] PMID:24274962
  11. Hoff AL, Kendall PC, Langley A, et al. Developmental differences in functioning in youth with social phobia. J Clin Child Adolesc Psychol. 2017;46(5):686–694. doi:10.1080/15374416.2015.1079779 [CrossRef] PMID:26630122
  12. Hicks BM, Johnson W, Durbin CE, Blonigen DM, Iacono WG, McGue M. Gene-environment correlation in the development of adolescent substance abuse: selection effects of child personality and mediation via contextual risk factors. Dev Psychopathol. 2013;25(1):119–132. doi:10.1017/S0954579412000946 [CrossRef] PMID:23398757
  13. Silberg J, Moore AA, Rutter M. Age of onset and the subclassification of conduct/dissocial disorder. J Child Psychol Psychiatry. 2015;56(7):826–833. doi:10.1111/jcpp.12353 [CrossRef] PMID:25359313
  14. Giannitelli M, Consoli A, Raffin M, et al. An overview of medical risk factors for childhood psychosis: implications for research and treatment. Schizophr Res. 2018;192:39–49. doi:10.1016/j.schres.2017.05.011 [CrossRef] PMID:28526280
  15. Price J, Kassam-Adams N, Alderfer MA, Christofferson J, Kazak AE. Systematic review: a reevaluation and update of the integrative (trajectory) model of pediatric medical traumatic stress. J Pediatr Psychol. 2016;41(1):86–97. doi:10.1093/jpepsy/jsv074 [CrossRef] PMID:26319585
  16. Marsac ML, Kassam-Adams N, Hildenbrand AK, et al. Implementing a trauma-informed approach in pediatric health care networks. JAMA Pediatr. 2016;170(1):70–77. doi:10.1001/jamapediatrics.2015.2206 [CrossRef] PMID:26571032

Rachel Ballard, MD, is an Attending Psychiatrist, Pritzker Department of Psychiatry and Behavioral Health, Ann & Robert H. Lurie Children's Hospital of Chicago; and a Professor of Child and Adolescent Psychiatry and of Pediatrics, Northwestern University Feinberg School of Medicine. Marisa Perez-Reisler, MD, is a Staff Psychiatrist, Pritzker Department of Psychiatry and Behavioral Health, Ann & Robert H. Lurie Children's Hospital of Chicago; and an Assistant Professor, Northwestern University Feinberg School of Medicine.

The authors thank the Pritzker Foundation for their support of our efforts to improve mental health care access and treatment.

Address correspondence to Rachel Ballard, MD, Ann & Robert H. Lurie Children's Hospital of Chicago, 225 E. Chicago Avenue, Box 10, Chicago, IL 60611; email:

Disclosure: Marisa Perez-Reisler discloses that her spouse is a consultant for Otsuka Pharmaceuticals. The remaining author has no relevant financial relationships to disclose.


Sign up to receive

Journal E-contents