Characteristics of autism spectrum disorders are associated with longer duration of anorexia nervosa: A systematic review and meta-analysis.

OBJECTIVE: Anorexia nervosa (AN) is associated with neuropsychological characteristics such as impairments in central coherence, cognitive flexibility, and emotion recognition. The same features also manifest in autism spectrum disorders (ASD) and have been suggested to be associated with illness prolongation in AN. The purpose of this meta-analysis was to examine whether pronounced neuropsychological characteristics related to ASD are associated with illness duration in AN. METHOD: Four databases (Medline, PsycINFO, Scopus, PubMed) were searched for eligible studies. Search terms were (a) "anorexia nervosa" and (b) "cognitive flexibility" or "set-shifting" or "central coherence" or "emotion recognition" or "theory of mind". The final sample consisted of 53 studies. Duration of AN was divided into three categories in order to investigate differences between the groups with varying illness duration. The meta-analysis was performed with Review Manager using a random-effects model. RESULTS: Deficits in central coherence, cognitive flexibility, and emotion recognition were pronounced among individuals with prolonged AN compared to those with shorter illness duration. DISCUSSION: A prolonged course of AN appears to be associated with underlying neuropsychological characteristics that are also distinctive to ASD. Neuropsychological impairments may lead to prolonged AN, and prolonged illness may contribute to the subsequent "neurological scar effect," further strengthening these impairments.

OBJETIVO: La Anorexia Nerviosa (AN) está asociada con características neuropsicológicas como alteraciones en la coherencia central, flexibilidad cognitiva, y reconocimiento de emociones. Las mismas características también se manifiestan en los trastornos del espectro autista (TEA), y se ha sugerido que se asocian con una prolongación de la enfermedad de la AN. El propósito de este meta-análisis fue examinar si las características neuropsicológicas pronunciadas relacionadas al TEA están asociadas con la duración de la enfermedad en la AN. MÉTODOS: Se investigó en cuatro bases de datos (Medline, PsycINFO, Scopus, PubMed) para encontrar estudios elegibles. Los términos de búsqueda fueron 1) "anorexia nerviosa", y 2) "flexibilidad cognitiva" o "cambio de un tipo de información a otro (set shifting)" o "coherencia central" o "reconocimiento de emociones" o "teoría de la mente". La muestra final consistió en 53 estudios. La duración de la AN fue dividida en tres categorías para poder investigar las diferencias entre los grupos con una duración variable de la enfermedad. El meta-análisis fue realizado con Review Manager utilizando un modelo de efecto aleatorio. RESULTADOS: Los déficits en la coherencia central, flexibilidad cognitiva, y el reconocimiento de emociones fueron más pronunciados en los individuos con AN prolongada en comparación con aquellos con una menor duración de la enfermedad. DISCUSIÓN: Un curso prolongado de AN parece estar asociado con características neuropsicológicas subyacentes que también son distintivas de los TEA. Las alteraciones neuropsicológicas pueden llevar a una AN prolongada y la enfermedad prolongada puede contribuir al posterior "efecto de cicatriz neurológica", reforzando aún más estas alteraciones.

Out of focus - Brain attention control deficits in adult ADHD.

Modern environments are full of information, and place high demands on the attention control mechanisms that allow the selection of information from one (focused attention) or multiple (divided attention) sources, react to changes in a given situation (stimulus-driven attention), and allocate effort according to demands (task-positive and task-negative activity). We aimed to reveal how attention deficit hyperactivity disorder (ADHD) affects the brain functions associated with these attention control processes in constantly demanding tasks. Sixteen adults with ADHD and 17 controls performed adaptive visual and auditory discrimination tasks during functional magnetic resonance imaging (fMRI). Overlapping brain activity in frontoparietal saliency and default-mode networks, as well as in the somato-motor, cerebellar, and striatal areas were observed in all participants. In the ADHD participants, we observed exclusive activity enhancement in the brain areas typically considered to be primarily involved in other attention control functions: During auditory-focused attention, we observed higher activation in the sensory cortical areas of irrelevant modality and the default-mode network (DMN). DMN activity also increased during divided attention in the ADHD group, in turn decreasing during a simple button-press task. Adding irrelevant stimulation resulted in enhanced activity in the salience network. Finally, the irrelevant distractors that capture attention in a stimulus-driven manner activated dorsal attention networks and the cerebellum. Our findings suggest that attention control deficits involve the activation of irrelevant sensory modality, problems in regulating the level of attention on demand, and may encumber top-down processing in cases of irrelevant information.

Predictive coding of phonological rules in auditory cortex: A mismatch negativity study.

The brain is constantly generating predictions of future sensory input to enable efficient adaptation. In the auditory domain, this applies also to the processing of speech. Here we aimed to determine whether the brain predicts the following segments of speech input on the basis of language-specific phonological rules that concern non-adjacent phonemes. Auditory event-related potentials (ERP) were recorded in a mismatch negativity (MMN) paradigm, where the Finnish vowel harmony, determined by the first syllables of pseudowords, either constrained or did not constrain the phonological composition of pseudoword endings. The phonological rule of vowel harmony was expected to create predictions about phonologically legal pseudoword endings. Results showed that MMN responses were larger for phonologically illegal than legal pseudowords, and P3a was elicited only for illegal pseudowords. This supports the hypothesis that speech input is evaluated against context-dependent phonological predictions that facilitate speech processing.