Memory strategy development in children with foetal alcohol spectrum disorders

Oral and written communication skills of adolescents with prenatal alcohol exposure (PAE) compared with those with no/low PAE: A systematic review

BACKGROUND

Prenatal alcohol exposure (PAE) is associated with growth deficits and neurodevelopmental impairment including foetal alcohol spectrum disorder (FASD). Difficulties with oral and written communication skills are common among children with PAE; however, less is known about how communication skills of adolescents who have PAE compare with those who do not. Adolescence is a critical time for development, supporting the transition into adulthood, but it is considered a high-risk period for those with FASD.

AIMS

We conducted a systematic review to synthesize evidence regarding oral and written communication skills of adolescents with PAE or FASD and how they compare with those with no PAE.

METHODS & PROCEDURES

A comprehensive search strategy used seven databases: Cochrane Library, Cinahl, Embase, Medline, PsycInfo, Eric and Web of Science. Included studies reported on at least one outcome related to oral and written communication for a PAE (or FASD) group as well as a no/low PAE group, both with age ranges of 10-24 years. Quality assessment was undertaken.

MAIN CONTRIBUTION

Communication skills most often assessed in the seven studies included in this review were semantic knowledge, semantic processing, and verbal learning and memory. These communication skills, in addition to reading and spelling, were commonly weaker among adolescents with PAE compared with those with no/low PAE. However, the findings were inconsistent across studies, and studies differed in their methodologies.

CONCLUSIONS & IMPLICATIONS

Our results emphasize that for adolescents with PAE, communication skills in both oral and written modalities should be comprehensively understood in assessment and when planning interventions. A key limitation of the existing literature is that comparison groups often include some participants with a low level of PAE, and that PAE definitions used to allocate participants to groups differ across studies.

WHAT THIS PAPER ADDS

What is already known on the subject PAE and FASD are associated with deficits in oral and written communication skills. Studies to date have mostly focused on children with a FASD diagnosis as well as combined groups of children and adolescents with FASD or PAE. There is a gap in what is known about oral and written communication skills of adolescents, specifically, who have PAE or FASD. This has implications for the provision of assessment and supports during a period of increased social and academic demands. What this study adds to existing knowledge This review provides systematic identification, assessment and synthesis of the current literature related to oral and written communication skills of adolescents with PAE compared with those with no/low PAE. The review revealed a small knowledge base with inconsistent methodologies and findings across studies. However, the findings overall highlight that adolescents with PAE have weaker skills in oral and written language than those with no/low PAE. Results are discussed in relation to education, social and emotional well-being, and forensic contexts. What are the potential or actual clinical implications of this work? Findings emphasize that for adolescents with PAE, comprehensive assessment of both oral and written communication skills, through both standardized and functional tasks, should be undertaken. Speech-language pathologists have a key role in assessment with individuals who have PAE.

Cross-Sectional Analysis of Spatial Working Memory Development in Children with Histories of Heavy Prenatal Alcohol Exposure

BACKGROUND

In children with prenatal alcohol exposure, spatial working memory is affected and brain regions important for spatial working memory performance exhibit atypical neurodevelopment. We therefore hypothesized that children with prenatal alcohol exposure may also have atypical development of spatial working memory ability.

METHODS

We examined the relation between spatial working memory and age using a cross-sectional developmental trajectory approach in youth with and without histories of heavy prenatal alcohol exposure. The Cambridge Neuropsychological Test Automated Battery Spatial Working Memory subtest was administered to children 5.0 to 16.9 years old.

RESULTS

While the controls and children with prenatal alcohol exposure showed similar performance at younger ages, larger group differences were observed in older children. This effect was replicated in a separate sample.

CONCLUSIONS

The atypical brain development that has previously been reported in children with heavy prenatal alcohol exposure may have clinically relevant implications for cognitive development; however, longitudinal cognitive analyses are needed.

Verbal learning and memory impairment in children with fetal alcohol spectrum disorders

BACKGROUND

Previous studies using the California Verbal Learning Test-Children's Version (CVLT-C) to examine effects of heavy prenatal alcohol exposure on verbal learning and memory have reported impaired information acquisition (i.e., encoding), rather than retrieval, as the primary mechanism underlying learning and memory impairment. We administered the CVLT-C to 2 independent cohorts to determine whether (i) effects on encoding are also seen at moderate exposure levels, using both categorical (diagnostic/exposure group) and continuous exposure measures; (ii) these deficits are specific or secondary to alcohol-related impairment in IQ; (iii) effects on retrieval can be detected over and above effects on initial encoding; and (iv) effects on learning are attributable to less efficient learning strategy use.

METHODS

We administered the CVLT-C and Wechsler Intelligence Scale for Children to 151 Cape Town heavy and nonexposed children (M = 10.3 years), and 291 Detroit adolescents recruited to over-represent moderate-to-heavy prenatal alcohol exposure (M = 14.4 years).

RESULTS

Effects on encoding in the heavily exposed Cape Town cohort and on retrieval in both cohorts were significant after adjustment for IQ. Although effects on retrieval were no longer significant in Cape Town after control for initial encoding, effects on recognition memory continued to be evident in Detroit. Children with full or partial fetal alcohol syndrome were less able to use the semantic cluster encoding strategy implicit in the CVLT-C.

CONCLUSIONS

Effects on verbal learning were seen primarily in the more heavily exposed Cape Town cohort; effects on recall and recognition memory were also seen at moderate exposure levels in Detroit. These effects were not attributable to alcohol-related impairment in overall intellectual competence. The finding that effects on retention continued to be evident after statistical adjustment for initial encoding in Detroit suggests that a fetal alcohol-related deficit in retrieval is not secondary to a failure to encode the initial information. These data confirm that this impairment in initial learning is mediated, in part, by failure to use the semantic cluster learning strategy.

Research Review: Executive function deficits in fetal alcohol spectrum disorders and attention-deficit/hyperactivity disorder - a meta-analysis

BACKGROUND

Attention-deficit/hyperactivity disorder (ADHD)-like symptoms are common in fetal alcohol spectrum disorders (FASD). FASD and ADHD groups both display executive function impairments; however, there is ongoing debate whether the pattern and magnitude of executive function deficits differs between these two types of disorders.

METHODS

An electronic literature search was conducted (PubMed, PsychInfo; 1972-2013) to identify studies comparing the executive functioning of children with FASD with ADHD or control groups. FASD groups included those with and without dysmorphy (i.e., FAS, pFAS, ARND, and other FASD diagnoses). Effect sizes (Hedges' g, standardized mean difference) were calculated. Random effects meta-analytic models were performed using the metafor package for R.

RESULTS

Fifty-one studies met inclusion criteria (FASD N = 2,115; ADHD N = 453; controls N = 1,990). Children with FASD showed the strongest and most consistent deficits in planning, fluency, and set-shifting compared to controls (Hedges' g = -0.94, -0.78) and children with ADHD (Hedges' g = -0.72, -0.32). FASD was associated with moderate to large impairments in working memory, compared to controls (Hedges' g = -.84, -.58) and small impairments relative to groups with ADHD (Hedges' g = -.26). Smaller and less consistent deficits were found on measures of inhibition and vigilance relative to controls (Hedges' g = -0.52, -0.31); FASD and ADHD were not differentiated on these measures. Moderator analyses indicated executive dysfunction was associated with older age, dysmorphy, and larger group differences in IQ. Sex and diagnostic system were not consistently related to effect size.

CONCLUSIONS

While FASD is associated with global executive impairments, executive function weaknesses are most consistent for measures of planning, fluency, and set-shifting. Neuropsychological measures assessing these executive function domains may improve differential diagnosis and treatment of FASD.

Cognitive factors contributing to spelling performance in children with prenatal alcohol exposure

OBJECTIVE

Heavy prenatal alcohol exposure is associated with impaired school functioning. Spelling performance has not been comprehensively evaluated. We examined whether children with heavy prenatal alcohol exposure demonstrate deficits in spelling and related abilities, including reading, and tested whether there are unique underlying mechanisms for observed deficits in this population.

METHOD

Ninety-six school-age children made up 2 groups: children with heavy prenatal alcohol exposure (AE, n = 49) and control children (CON, n = 47). Children completed select subtests from the Wechsler Individual Achievement Test-Second Edition and the NEPSY-II. Group differences and relations between spelling and theoretically related cognitive variables were evaluated using multivariate analysis of variance and Pearson correlations. Hierarchical regression analyses were used to assess contributions of group membership and cognitive variables to spelling performance. The specificity of these deficits and underlying mechanisms was tested by examining the relations between reading ability, group membership, and cognitive variables.

RESULTS

Groups differed significantly on all variables. Group membership and phonological processing significantly contributed to spelling performance, whereas for reading, group membership and all cognitive variables contributed significantly. For both reading and spelling, group × working memory interactions revealed that working memory contributed independently only for alcohol-exposed children.

CONCLUSION

Alcohol-exposed children demonstrated a unique pattern of spelling deficits. The relation of working memory to spelling and reading was specific to the AE group, suggesting that if prenatal alcohol exposure is known or suspected, working memory ability should be considered in the development and implementation of explicit instruction.

Playfulness and prenatal alcohol exposure: a comparative study

BACKGROUND/AIM

South Africa carries a high burden of alcohol abuse. The effects of maternal alcohol consumption during pregnancy are most pronounced in poor, rural communities. Earlier research suggests that children with prenatal alcohol exposure have poor social behaviour; however, to date, no research has investigated their playfulness. This study investigated the differences in playfulness of children with and without prenatal alcohol exposure.

METHODS

Grade one learners with a positive history of prenatal alcohol exposure (n = 15) and a reference group without a positive history of prenatal alcohol exposure (n = 15) were filmed engaging in free play at their schools. The Test of Playfulness was used to measure playfulness from recordings. Data were subjected to Rasch analysis to calculate interval level measure scores for each participant. The overall measure scores and individual Test of Playfulness social items were subjected to paired samples t-tests to calculate if significant differences existed between the groups.

RESULTS

Children with prenatal alcohol exposure had a significantly lower mean overall playfulness score than the reference group (t = -2.51; d.f. = 28; P = 0.02). Children with prenatal alcohol exposure also scored significantly lower than the reference group on 5 of the 12 Test of Playfulness items related to social play.

CONCLUSIONS

This research suggests that children with prenatal alcohol exposure are more likely to experience poorer overall quality of play, with particular deficits in social play. Considering play is a child's primary occupation, this finding becomes pertinent for occupational therapy practice, particularly in post-apartheid South Africa, where high prenatal alcohol exposure prevalence rates are couched within persistent socio-economic inequalities.

Motion perception in children with foetal alcohol syndrome

AIM

To evaluate the visual magnocellular pathway by a coherent motion perception test in children with foetal alcohol syndrome (FAS).

METHODS

Eighty-nine children (49 with verified FAS and 40 without FAS) aged from 10 to 16 years were included into the study. Both the study and the control group were children living in orphanages. A coherent motion perception test was used. The test consisted of 150 white moving dots on a black background presented in different signal-to-noise ratio conditions. The task was direction detection of the coherently moving dots whose percentage decreased at each step.

RESULTS

A significant difference between the two groups was found (p = 0.018). Children with FAS had lower coherent motion perception ability in all the signal-to-noise ratio conditions. A significant difference between difficulty levels (p < 0.001) was found for all subjects in both groups - decreasing the stimulus signal-to-noise level decreased the motion perception score. In both groups, the motion perception score differed for vertical and horizontal stimuli (p = 0.003) with better performance with vertical stimuli.

CONCLUSION

Impaired motion perception in FAS children could be indicative of a dorsal stream developmental dysfunction resulting from alcohol brain damage.