Orofacial clefts are a group of congenital craniofacial deformities characterized by structural defects within and around the oral cavity. While some orofacial clefts are associated with an identifiable genetic or teratogenic syndrome, most are isolated or nonsyndromic. It has been well-documented that children born with nonsyndromic cleft lip and/or palate (NCL/P) are at-risk for poorer academic outcomes, especially within reading. Research into the cognitive functioning of patients with NCL/P has demonstrated that auditory-verbal memory and rapid naming are significant neuropsychological predictors of their lower reading achievement. Despite a solid compendium of research into the reading outcomes of those affected by NCL/P, very little research into the mathematical skills of this population exists.
The current study examined whether the arithmetical computation skills of children, adolescents, and young adults with NCL/P differ significantly from healthy control participants. Comparisons of potential neuropsychological predictors of arithmetical computation were also conducted to determine whether these variables differ significantly for participants with NCL/P. Given the influence of language on both reading and mathematics and clear evidence of language impairments in individuals with NCL/P, it was hypothesized that arithmetical computation would be significantly lower for the NCL/P group. It was also hypothesized that the neuropsychological variables associated with lowered reading in NCL/P would be the strongest predictors of arithmetical computation. Results confirmed that arithmetical computation was significantly lower for the NCL/P group. Sustained attention, visual-spatial organization, auditory-verbal memory and rapid naming were significant predictors for the NCL/P group; rapid naming was the lone variable that was significantly more predictive of arithmetical computation for the NCL/P group than for control participants. These results suggest that inefficient verbal label retrieval related to short-term memory deficits underlie the computational difficulties of individuals with NCL/P. These findings have implications for approaches to remediation, as well as future research.