Behavioral and Socio-Emotional Disorders in Intellectual Giftedness: A Systematic Review

Eight studies investigated socio-emotional problems in intellectual giftedness. Among the four studies involving children, two studies [29, 34] revealed the presence of socio-emotional problems in the gifted group. Two studies focused on adolescents, and one of them [41] found socio-emotional problems. One study [33], which was addressed to both children and adolescents, did not reveal the presence of problems related to the socio-emotional area. Finally, only one study [26] investigated adults and found no socio-emotional difficulties. More details are provided below.

Peyre et al. [30] investigated the presence of socio-emotional problems, reported on the parent-rated SDQ, by comparing gifted and non-gifted preschool children (5–6 years old) recruited in a general population mother-child cohort. They did not find between-group differences in items investigating peer relationships (e.g., isolation and ability to relate to peers compared to adults) and prosocial behaviors (e.g., consideration of others, willingness to comfort others). Using the SDQ, the authors investigated the presence of internalizing and externalizing problems as well. No significant differences with the control group emerged again. This study suggests that children with high IQ, recruited in the preschool age among the general population, did not show problematic behaviors. In contrast, the study of Guénolé et al. [29], which compared scores on parent-rated CBCL of clinically-referred gifted school children, aged 8 to 12, to scores of age- and sex-matched group of children recruited at school, revealed that gifted children displayed increased behavioral problems in the whole symptomatic range, including withdrawn and social domains.

Eren et al. [33] assessed social behaviors in gifted children and adolescents (9–18 years) attending a special school, and in a control group of participants of a regular school, using multiple instruments, namely, the K-SADS-PL, the SDQ, and the Pediatric Quality of Life Inventory (PedsQL; [54]), completed by parents and children (adolescent only in the case of SDQ). No significant differences between groups were found, in parents’ and children’s scores. Similarly, the group of gifted children and pre-adolescents of Guignard et al. [34], recruited at school with special classes, did not differ from the non-gifted control group, matched for education grade, in the “social concerns” score of the R-CMAS. Nevertheless, they exhibited significantly more social concerns than the non-gifted control group matched for age.

Lacour & Zdanowicz [41] found that gifted adolescents between 12 and 16 years reported having fewer friends in real life and fewer virtual friends compared to a non-gifted group, as assessed by the K-SADS-PL and the School Refusal Assessment Scale-Revised [55, 56]. The majority of them considered themselves shy, unsure of themselves, and experienced fear of social situations. Furthermore, they reported more irritability, negative affect, distractibility, and separation anxiety. On the other hand, they reported higher family cohesion in the Family Adaptability and Cohesiveness Evaluation Scale III [57] questionnaire. The authors attributed this latter evidence to a potential disincentive for them to open up and decrease their shyness.

On the other hand, Chung et al. [32] found a significantly higher cooperative tendency in gifted adolescents compared to non-gifted adolescents in a multi-player social interaction game, especially when cooperation was rewarded.

Karpinski et al. [26], using an online survey, asked gifted adult participants to indicate if they had been diagnosed with one or more disorders among a list (bipolar disorder, depressive disorder, generalized anxiety, social anxiety, obsessive-compulsive disorder, Asperger’s syndrome). Then, they compared the responses with those obtained from previous national surveys. A higher prevalence of disorders emerged in the gifted group. Social anxiety was the only domain in which differences were not found.

Internalizing problems were investigated the most (9 studies out of 19). Of these studies, six involved children, four of which [28, 29, 34, 38] revealed the presence of internalizing problems in the gifted group; two studies [33, 41] involved adolescents as well and found no internalizing problems. The study that involved adults [26] found an association between intellectual giftedness and internalizing problems.

In 5–6 years old children, Peyre et al. [30] found no association between intellectual giftedness and anxiety or depressive symptoms, rated by parents in the SDQ. Guignard et al. [34] assessed anxiety and perfectionism in gifted children in 6th grade, using the self-rated R-CMAS in conjunction with the Children and Adolescent Perfectionism Scale (CAPS; [58]). It turned out that gifted children did not differ from the non-gifted grade-matched group on R-CMAS scores. Nevertheless, they tended to exhibit higher scores on the worry/overexcitability scale than the non-gifted age-matched (5th grade) group. Also, they showed the same level of perfectionism as their age peers (in all CAPS scores) and a higher level of perfectionism than their grade peers (in the total CAPS score and in the self-oriented dimension). In conclusion, the gifted children were closer to their grade level peers than to their same-age peers in some internalizing behaviors.

Kermarrec et al. [38] found that children with IQ ≥ 130 compared to children with IQ < 130 showed more anxiety disorders, which mainly included generalized anxiety disorder, phobic anxiety disorder and separation anxiety disorder (ICD-10), diagnosed by the child psychiatrist. Moreover, the authors found that children with verbal comprehension (VCI) scores ≥ 130 described themselves as more anxious on the R-CMAS (total anxiety, physiological anxiety and worry/oversensitivity scores) than children with lower IQ scores. In contrast, children with perceptual reasoning (PRI) scores ≥ 130 stated themselves as less anxious. This study raised the issue that different domains of excellence (either verbal or non-verbal) might have other behavioral correlates in daily life.

Shaywitz et al. [28] found higher scores on the negative affect scale of the Yale Children’s Inventory (YCI; [59]) (e.g., rejection by peers, depression, pessimism) in the gifted group compared to the non-gifted group of children, both groups including boys only. Interestingly, in this study, differences between “low-gifted” and “high-gifted” children were investigated. Moreover, a group with learning disabilities was added. The low-gifted group (IQ range: 124–139) presented a behavioral pattern similar to that one of the non-gifted group on all behavioral measures, whereas, the high-gifted group (IQ range: 140–154) presented a behavioral pattern similar to that one of the children with learning disabilities, characterized by hyperactivity and distractibility. When comparing low-gifted (IQ range: 130–145) vs. high-gifted (IQ ≥ 145) children, Guénolé et al. [29] found that the first group did not show more internalizing symptoms (16.7%) than the second group (10.3%). However, “low giftedness” was associated with more somatic disorders than “high giftedness”. Beyond the contrasting findings, the two latter studies revealed that the “level” of intellectual giftedness might impact behavior.

Richards et al. [35] examined a group of gifted and a group of non-gifted pre-adolescents and adolescents using the BASC. Teachers’ ratings revealed no significant differences between the groups. On the other hand, parents’ ratings revealed that the gifted group showed lower levels of anxiety and attention problems than the non-gifted group, demonstrating a better overall psychological adjustment. Furthermore, self-report scores of the gifted group on the depression scale and on the sense of inadequacy scale were significantly lower than their average ability peers, indicating better emotional adjustment and less inadequacy, respectively. This study highlights the importance of comparing ratings from multiple observers. In line with this, Eren et al. [33] investigated a wider age-range sample (from 9 to 18 years). They did not find differences in anxiety and depressive symptoms between the gifted and the non-gifted group of children when considering parents’ ratings (K-SADS, SDQ, PedsQL) as well as child’s ratings (K-SADS, SDQ to adolescents, PedsQL, State-Trait Anxiety Inventory for Children [60], Child Depression Inventory [61]) and clinician evaluation (Children Depression Rating Scale-Revised – CDRS-R [62]). On the parent-rated Family Assessment Device [63], family members of gifted children showed more care for each other than the non-gifted group.

In adulthood, Karpinski et al. [26] found that the gifted participants showed an increased rate of mood disorders (mood disorders, bipolar disorder, other mood disorders) and anxiety disorders, such as generalized anxiety disorder and obsessive-compulsive disorder than the national average.

Few studies (5 out of 19) examined externalizing problems related to giftedness, such as hyperactivity and oppositional behaviors. As specified below, these studies provided inconsistent evidence.

Peyre et al. [30] found no difference in hyperactivity/inattention and conduct problems between gifted and non-gifted preschool children, as rated by parents in the SDQ. Shaywitz et al. [28] found more problems of tractability (e.g., needing constant supervision, difficulty with babysitters and with visiting friends) in high-gifted age-school children compared to low-gifted children and non-gifted children, as reported by parents in the YCI. Eren et al. [33] reported more inattention/hyperactivity problems in the gifted group relative to the non-gifted group, as revealed by the child-rated SDQ. Also, Guénolé et al. [29] showed more externalizing problems (delinquent and aggressive behavior). More specifically, low-gifted children displayed more mixed syndromes than high-gifted children. Interestingly, mean CBCL raw scores between gifted children with and without a significant verbal-performance discrepancy (SVPD) on the Wechsler Intelligence Scale for Children (WISC) were compared. The subgroup of gifted children with SVPD showed higher scores in externalizing problems, aggressive behavior, and mixed syndrome than gifted children without this discrepancy.

In contrast, in a general population-based study (n = 2221) of 10–12 years old children, Rommelse et al. [42] did not find an increased rate of externalizing problems in a gifted group of children and pre-adolescents compared to non-gifted controls, as assessed by the parent-, teacher- and self-rated instruments (i.e., CBCL, Teacher’s Report Form, and Youth Self-Report).

The association between intellectual giftedness and ADHD symptoms was the most investigated comorbidity (9/19 studies). Six studies compared groups of gifted children with a diagnosis of ADHD with groups of gifted children without ADHD. Chae et al. [31] found that gifted children with ADHD obtained poorer scores on the CBCL social competency scale compared to both gifted children without ADHD and non-gifted children. Unfortunately, this study has a limited sample size of children with ADHD in the gifted group, therefore this comparison should be taken cautiously.

Antshel et al. [36] showed that gifted children with a diagnosis of ADHD were more likely to have psychopathological comorbidities (according to the CBCL scales), to repeat a grade, and to show functional impairments in all social domains (according to the Social Adjustment Inventory for Children and Adolescents, SAICA scales [64]), such as in the relationships with peers, with the opposite sex, and with parents. On the other hand, they carry on significantly more activities in their spare time and with their father. The K-SADS interviews with mothers and with children (older than 12 years) revealed a lifetime history of multiple disorders, namely, depression, generalized anxiety, separation anxiety, social phobia, simple phobia, oppositional defiant, and conduct disorders [36]. The follow-up study [19], conducted 4.5 years later, demonstrated that the differences in psychopathological comorbidities between high-IQ children with ADHD and high-IQ children without ADHD persisted over time, with significantly higher rates of depression, separation anxiety, social phobia, simple phobia, oppositional defiant and obsessive-compulsive disorders. The ADHD status was still a significant predictor of higher functional impairment across social, academic, and family domains. Since the studies of Antshel et al. lacked a non-gifted control group, we compared the average scores of the gifted participants without ADHD with the normative cut-offs [64, 65]. We found that in Antshel et al. [36] they obtained higher scores in all subscales of the CBCL and in the subscales that assess problems in spare time in SAICA. In contrast, in the follow-up study [19], they reported lower scores than the normative mean in all the SAICA subscales (except for boy-girl relationships). This finding could reflect a remission of functional impairments.

Foley-Nicpon et al. [40] compared two age-matched gifted groups of children and adolescents, with and without ADHD. The ADHD group reported lower positive self-esteem (BASC-2), lower self-concept about their behavior, and worse overall happiness (Piers–Harris Self-Concept Scale 2 [66]). On the other hand, they showed neither differences in the perception of relationships with others, intelligence, and physical attributes, nor differences with regards to self-reported symptoms of anxiety, popularity, self-reliance, or social stress.

As high-IQ children with ADHD, high-IQ adults with ADHD reported higher rates of major depressive disorder, generalized anxiety disorder, and obsessive-compulsive disorder, compared to high-IQ adults without ADHD [25]. Moreover, they reported lower quality-of-life ratings (in Quality of Life Enjoyment and Satisfaction Questionnaire, Q-LES-Q [67]) and more functional impairments across a variety of occupational, social and family domains (in Social Adjustment Scale-Self-Report [68]). The authors attributed these symptoms to the stress deriving from high intelligence and a clear understanding of the potential consequences, in the context of impulsivity and lack of executive control. In contrast, other psychiatric comorbidities, such as substance abuse disorders, alcohol abuse, or antisocial personality disorder, did not differ between gifted groups with and without ADHD. When we compared the gifted adults with ADHD of Antshel et al. [25] to similar non-gifted participants with ADHD in another study by Mick et al. [69], we found better ability to get around without dizziness in the first group. On the other hand, the gifted adults without ADHD of Antshel et al. [25] had lower scores on Q-LES-Q in physical health, in the ability to get around without dizziness compared to the study by Mick et al. [69]. Still, they had higher scores in household activities, social relationships, leisure time, living/housing situations, and overall life satisfaction. This finding would suggest that the quality of life in gifted adults with ADHD might be better in some domains, such as social relationships, than in non-gifted adults with ADHD.

A more recent study compared two groups of gifted children, with and without ADHD, to two groups of non-gifted age-matched children, with and without ADHD [39]. In the Strengths and Weaknesses of Attention-Deficit/Hyperactivity Disorder Symptoms and Normal Behavior Scale (SWAN [70]), the two groups without ADHD did not differ in inattention, hyperactivity/impulsivity, and total ADHD scores. Conversely, both gifted and non-gifted groups with ADHD had higher average scores than the gifted and non-gifted groups without ADHD. Notably, the non-gifted group with ADHD reported higher scores than the gifted with ADHD group for all inattention symptoms; the opposite pattern was found for some hyperactivity/impulsivity behaviors (modulation of motor activity, modulation of verbal activity, and reflecting on questions). Compared to non-gifted children with ADHD, children with ADHD may be more often hyperactive than inattentive. Additional investigations comparing gifted children with ADHD with gifted children without ADHD are needed to clarify whether giftedness may attenuate or exacerbate ADHD symptoms.

A separate consideration has to be made for the studies that examine the presence of ADHD symptoms in high-IQ individuals. Rommelse et al. [42] found that the IQ scores in a children population were inversely related to attention and hyperactivity/impulsivity problems. However, high discrepancies among parents’ and teachers’ ratings emerged in cases with extreme IQ values. Namely, parents reported more attention problems in children with high IQ, whereas teachers reported more attention problems in children with low IQ. According to the authors, the type of environment, more or less stimulating, plays a major role in determining attention problems: since the school is a cognitively more stimulating environment than the home, it could elicit fewer attention problems in highly intelligent children.

McCoach et al. [27] investigated the presence of inattention and hyperactivity/impulsivity problems in gifted children and adolescents, according to the ADHD-IV rating scales [71] scored by parents and teachers. Both raters reported significantly greater inattention problems in the gifted compared to the non-gifted group, with greater frequency in the classroom than at home. The gifted children with higher inattention scores were also those with lower scores in goal-valuation, self-efficacy and, most importantly, self-regulation measured by the School Achievement Attitudes Survey-Revised [72]. Furthermore, they showed lower academic grades. In line with Rommelse and coworkers, the authors suggested that context-specific inattention in intellectual giftedness would be attributed to boredom or lack of a stimulating environment, more than to ADHD.

Surprisingly, among the studies included in the present review only one study examined the association with ASD, although this is commonly observed in clinical settings. Specifically, Doobay et al. [37] investigated adaptive and psychosocial functioning in gifted participants with ASD (from 5 to 17 years). A multi-informant instrument was adopted (the BASC-2), and an inter-rater discrepancy emerged across self-assessment, parents’ and teachers’ assessment. According to parents’ reports, the gifted ASD group had significantly higher scores than the gifted non-ASD group on almost all scales (aggression, attention, atypicality, depression, hyperactivity, somatization, and withdrawal). In particular, mean scores on the atypicality and withdrawal were above the clinical cut-off. Also, parents’ ratings on communication, daily living, and socialization skills in the Vineland Adaptive Behavior Scales [73] were significantly worse in the ASD than in the non-ASD group. These results suggested to the authors that the presence of an ASD comorbidity altered the socio-emotional and behavioral patterns in giftedness. Similar results were observed in the teachers’ reports, although no scores above the clinical cut-off were obtained. According to the authors, gifted children/adolescents interacting with adults more than peers is sometimes not deemed as a social deficit, but a sign of maturity, sophistication, or intellect. On the other hand, young intellectually gifted people with ASD may better understand and have more awareness of their psychosocial challenges. Therefore, they may be more able to express and articulate socio-emotional difficulties, such as depression or inattention, than their ASD peers with lower intellectual functioning do. Unfortunately, since a control group of non-gifted children with an ASD diagnosis was missing in the study, the hypothesis that intellectual giftedness might attenuate behavioral problems remains unaddressed. In contrast to parents’ and teachers’ reports, self-reports did not differentiate gifted participants with and without ASD. Moreover, a more positive picture of emotion regulation skills emerged in the first group of participants. Of note, all scores rated by all informants in the gifted non-ASD group were in the normal range. This means that gifted children, adolescents, and teens were no more likely than their peers to suffer social or emotional difficulties.