The Impact of Childhood Neglect on Cognition in School-Aged Children

Childhood neglect is the most ubiquitous and prevalent form of adverse childhood experiences (ACEs). Given the significance of cognitive function and its malleability in retort to environmental stimuli, there is significant relevance in understanding the impact of child neglect on cognitive domains. Furthermore, examining the cognitive domains individually enables a more nuanced understanding of the impact of childhood neglect. This article details a scoping review undertaken to explore the relationship between childhood neglect and cognitive function, with the aim to recognize the observable cognitive qualities in neglected children, in the absenteeism of other ACEs. Cognitive function was divided into five domains: executive function, academic achievement, language, memory and intelligence. The findings demonstrated that executive function (working memory and attention shifting), language and intelligence were associated with childhood neglect, and there was no association between executive function (spatial planning), academic achievement, memory and childhood neglect.

Once neglected children start in education, indicators of academic concern rapidly appear Peterson (2013) et al. [3].
Academic achievement signifies performance outcomes that signify the degree to which a child has completed educational objectives Woolfolk (2007) [18]. In a longitudinal study, neglected children in kindergarten were regarded by their teachers as having more trouble understanding school tasks, compared to children who had not been neglected Erickson (1989) et al. [19]. By second grade, most of the neglected children had been referred to special education services Egeland (1991) [20]. This display of academic difficulties increased during their school years and was seen through into adolescence Egeland (1997) [21].
Moreover, childhood neglect and the impact on the language domain has been previously studied Eigsti (2004) [21]. Language is a structured system of communication and involves skills such as listening and reading (receptive skills) and writing and speaking (productive skills; Trask (2007) [22]). Language delay becomes more evident as children grow older, with research finding that neglected children demonstrated more syntactic delays and reduced vocabulary than control groups [23]. Language delay is also apparent when child maltreatment types are compared. Children who had been neglected had more delays in receptive language (auditory comprehension) and expressive language (verbal ability) than children who had been physically abused Allen (1982) et al. [24]; Culp (1991) [25].
This article details a scoping review that was undertaken to explore the relationship between childhood neglect and cognitive function. To recognize the observable cognitive qualities in neglected children, in the absenteeism of other ACEs, to gain a better understanding of the behaviours they may exhibit.

Aim
To provide a comprehensive overview of the impact of childhood neglect on cognition in school-aged children.

Method
The process and results reporting were guided by the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines, 2009 revision Moher (2009) [30].
Truncation symbols and the boolean operator ' AND' was used in the advanced search strategy to link the different groupings of search terms (S1 AND S2 AND S3).
The inclusion criteria were that the studies had to: a) Be peer-reviewed research. b) Involve school-aged children (

Findings
The first stage of analysis was assessing the heterogeneity of the included articles. A high heterogeneity among these characteristics of included articles precluded the use of a meta-analysis. This is because high heterogeneity violates the underlying assumption of a normal distribution Higgins (2009) [34]. As recommended by the Cochrane review/collaboration Higgins (2019) [35] a narrative synthesis was used to explore the relationship between childhood neglect and cognitive function.
To provide a comprehensive review, cognitive function was divided into five subcategories: executive function, academic achievement, language, memory and intelligence Yingying (2019) [28]. Once all the articles had been grouped into subcategories, this made it substantially easier to explore the relationships within and between articles. Further grouping occurred for studies that used the same neurocognitive tests.

Executive Function
Executive function was divided into working memory, attention shifting and spatial planning. Whether executive function ought to be conceptualized as a unitary concept or several separate functions has been a matter of discussion Stuss and Alexander (2000) [36]. However, further research suggests executive function is best considered as distinct functions Blair (2005) et al. [37].

Working Memory
Using the Cambridge Neuropsychological Test and Automated Battery (CANTAB), spatial working memory task, one study

Academic Achievement
Two studies used school grades to assess academic achievement.
One study Manly (2013) et al. [42] found that childhood neglect was associated with diminished language arts, in kindergarten. Neglect was also associated with mathematics results, in first-grade, and poorer results in general in first-grade academic achievement.
Nevertheless, neglect severity was found to not be directly related to first-grade academic achievement, but rather indirectly associated with cognitive function. However, McGuire and Jackson (2018) [43] found that emotional abuse severity and physical abuse was a significant predictor of English grades. Neglect was found to not be a significant predictor of grades and no variables predicted  [45]. Both studies focused on older children and who had been in foster care [41] or in out-of-home care [42]. Whereas, manly who found that childhood neglect was associated with language arts and mathematics, focused on younger children and those recruited through the Department of Health Services (DHS).
Given the variances in data collections techniques, for example, how neglect was recorded, inconsistencies between studies are common. These discrepancies partially explain differences in association with academic functions [43]. Moreover, another reason for the discrepancy in study's findings could be due to the variation of what is deemed as academic achievement. From the included articles, given that there were mixed results and more studies found no association, this review will accept that childhood neglect is not associated with academic achievement. The included articles in this review, found mixed results when it came to the association between childhood neglect and language.

Language
An explanation for the studies that found no association could be due to the measurement tool used. Despite the CELF's effort to formulate a comprehensive language tool, it lacks validity due to a misleading standardized sample and an inadequate reference standard Paslawski (2007) [49]. There is also an absence of data as to how items and tasks are considered appropriate. As the CELF is mainly vocabulary based, it will tend to recognize the socioeconomic status and second language acquisition concerns, rather than language development concerns, due to the significant linguistic, cultural and socioeconomic bias [49]. These concerns with the CELF could explain why the two studies De Bellis et al. [46,47] in this review found no association between neglect and language. Therefore, this review will accept that childhood neglect is associated with language.
The studies that used the California Verbal Learning Test (CVLT) found that memory ability in children who had been neglected or abused was no different to children in the control group Cicchetti (2010) [50]. Cicchetti

Intelligence
All studies recognized a negative association between childhood neglect and IQ scores even after adjusting confounders. One study Bengwasan (2018)  in this review found there was an association between child neglect and intelligence. Therefore, this review will accept that childhood neglect is associated with intelligence.

Discussion
The findings from this review provided evidence that child neglect is associated with cognitive function and does have an impact on domains such as executive function (working memory and attention shifting), language and intelligence. However, the articles included in this review also found no association between neglect and executive function (spatial planning), academic achievement and memory. Although the findings from the 13 included articles found mixed results with regards to the association between child neglect and cognitive function. It is clear from the findings and previous research the difficulties that children with neglect face, from poverty to a lack of parental care, impacting their growth and well-being Rutter and Sroufe, (2000). This demonstrates the detrimental effects of not just neglect, but ACEs in general.

Limitations
In the included studies, the definition of neglect was highly variable. This made it difficult to make comparisons and similarities between the studies. Due to high heterogeneity, this precluded the use of a meta-analysis and justified the use of narrative synthesis Higgins (2009) [33]. It could be argued if there is no single operational definition for neglect, this makes it challenging to interpret and compare the findings of the research and to establish whether children are eligible for services. Moreover, in many of the included studies, the use of a wide range of age groups meant it was impossible to make comparisons and similarities between the studies. It can be argued that different regions of the brain develop at different stages. Therefore, this may be the reason there is a difference between two studies using different age bands, instead of it being as a result of childhood neglect.

Recommendations for Practice
Several recommendations for education professionals can be made based on the findings of this scoping review.
Understanding the nature and frequency of ACEs in school-aged children, particularly at a young age (6-12 years of age) can guide teachers who feel they lack the knowledge of indicating neglect.
By recognizing neglect and intervening early, teachers can help children who have been neglected to attain better performance in school. Recognising the impact of neglect on children can help to understand why classrooms can be challenging and upsetting places for these children. Consistent with the findings from this review and previous research, neglected children have enhanced problem solving and spatial planning skills, so these children may sometimes be seen as more independent than other children Maguire et al. (2015) [7]. At the same time, they may also have difficulty with classroom routines and other elements. Therefore, if teachers are aware of these styles of cognitive features, then child neglect can be recognized early on. Moreover, by understanding childhood neglect in school-aged children, research can help to justify the allocation of resources at a widespread level within a multitiered framework [54].

Conclusion
It is hoped that the results of this review will offer support for a universal definition of childhood neglect. Moreover, by understanding childhood neglect in school-aged children can also help to build on teachers knowledge of neglect and justify the allocation of resources at a widespread level within a multitiered framework.