Cognitive, Behavioral, and Emotional Manifestations in Nodding Syndrome: A Neuropsychological Narrative Review.

Abstract

Background: Nodding syndrome is a childhood-onset epileptic encephalopathy described in onchocerciasis-endemic regions of sub-Saharan Africa. Although characterized by recurrent atonic seizures with repetitive head-nodding movements, increasing evidence suggests that the condition extends beyond a purely motor epilepsy and involves progressive cognitive, behavioral, and emotional impairment.

Methods: This study was designed as a narrative review with a specific neuropsychological focus. A literature search was conducted in PubMed, Scopus, and Google Scholar for publications between 2013 and 2025. Studies describing cognitive, behavioral, emotional, psychiatric, neuroimaging, or neuropathological findings in patients with nodding syndrome were included. Due to heterogeneity in study design and assessment methods, findings were synthesized narratively.

Results: Across studies, nodding syndrome is consistently associated with progressive cognitive decline affecting attention, processing speed, executive functions, memory, and global intellectual functioning. Behavioral disturbances such as irritability, aggression, and emotional lability are frequently reported, alongside depressive symptoms and social withdrawal. Neuroimaging findings commonly demonstrate cortical and cerebellar atrophy, while neuropathological studies report tau-protein deposition and neuronal loss, supporting diffuse cerebral involvement with possible neurodegenerative features.

Conclusions: Nodding syndrome represents a complex epileptic encephalopathy characterized not only by seizures but also by significant cognitive, behavioral, and emotional impairment. A clearer neuropsychological characterization may inform clinical assessment and guide future research aimed at improving supportive and rehabilitative interventions.