Attentional shifting and disengagement in Rett syndrome

Area of Science:

• Cognitive Neuroscience
• Neurodevelopmental Disorders
• Genetics

Background:

• Rett syndrome (RTT) is an X-linked neurodevelopmental disorder caused by MECP2 gene mutations.
• Attention is a core cognitive ability crucial for environmental exploration.
• Visual orienting, encompassing attention shifting and disengagement, is vital for processing visual information.

Purpose of the Study:

• To investigate attention shifting and disengagement in children with Rett syndrome.
• To utilize eye-tracking technology to assess visual orienting in RTT, minimizing motor and verbal demands.
• To deepen the understanding of cognitive abilities in Rett syndrome.

Main Methods:

• The study included 31 children with Rett syndrome (RTT) and 31 typically developing (TD) controls (ages 2-12).
• The gap-overlap paradigm was employed to measure the frequency and speed of attention shifting.
• Eye-tracking quantified saccadic reaction times (SRTs) on baseline and overlap trials to assess attention shifting and disengagement.

Main Results:

• Children with RTT demonstrated significantly more 'sticky fixations' than TD controls, indicating difficulty shifting attention.
• Saccadic reaction times (SRTs) were slower in younger children with RTT compared to TD peers.
• While attention shifting was impaired, the cost of disengaging attention did not significantly differ between groups.

Conclusions:

• Children with Rett syndrome exhibit notable difficulties in shifting visual attention.
• Impaired attention disengagement is present but appears less pronounced than attention shifting deficits in RTT.
• Findings highlight specific attention-related challenges in RTT, differentiating it from other neurodevelopmental disorders.