A comparison of affective information processing in Noonan and Turner syndromes: Evidence of alexithymia

Objective: Noonan (NS) and Turner syndrome (TS) are associated with cognitive problems and difficulties in affective information processing. While both phenotypes share physical features, genetic etiology and neuropsychological phenotype differ significantly. The present study examines putative differences in affective information processing and social cognition of patients with NS and TS. Participants and Methods: Two groups of female patients (27 NS, 40 TS) and 40 female controls were matched on age and intelligence, and subsequently compared on (a) alexithymia, measured by the Bermond Vorst Alexithymia Questionnaire, (b) emotion recognition, evaluated by the Emotion Recognition Task (ERT), and (c) social cognition, assessed by the Scale of Interpersonal Behaviour as well as a social cognition factor (SCF) based on subtests of the WAIS-III. Results: Impaired affective information processing was present in the TS group (alexithymia: p-values<.001; ERT happiness: p<.01; SCF: p<.05) compared with the NS group, whereas patients with NS only had more difficulty in the recognition of angry facial expressions than controls (p=.01). Conclusions: Impairments in affective information processing, in particular alexithymia, are more pronounced in patients with TS than in NS. Visuospatial difficulties, typically associated with TS, may explain the results found on the SCF. In NS, some indications were found for sex-specific patterns of alexithymia. Present findings of differential profiles in NS and TS suggest neuropsychological phenotyping to be helpful for the diagnosis of specific cognitive-affective deficits in genetic syndromes, and for the development of personalised treatment.