Insights into cognitive decline in spinocerebellar Ataxia type 2: a P300 event-related brain potential study

Roberto Rodríguez‐Labrada; Luis Velázquez‐Pérez; Ortega-Sánchez, Ricardo; Peña-Acosta, Arnoy; Yaimeé Vázquez‐Mojena; Nalia Canales‐Ochoa; Jacqueline Medrano‐Montero; Reidenis Torres‐Vega; González-Zaldívar, Yanetza · 2019 · OpenAlex-citations

DOI: 10.1186/s40673-019-0097-2

archive: archived pipeline: cataloged verified

Get this paper ↗ (DOI — opens at the source; we link to it, we don't host it)

Summary

This study investigates cognitive decline in Spinocerebellar Ataxia type 2 (SCA2), a neurodegenerative disorder characterized by cerebellar degeneration and early cognitive dysfunction. The research aims to evaluate P300 event-related potentials (ERPs) as surrogate biomarkers for cognitive impairment, assessing their utility from the prodromal stage through symptomatic disease. The motivation stems from the lack of effective neuroprotective treatments and the need for objective outcome measures for future clinical trials, particularly given that cognitive deficits often precede motor symptoms. The researchers conducted a cross-sectional study involving 30 clinically diagnosed SCA2 patients, 20 preclinical carriers with the SCA2 mutation but no cerebellar syndrome, and 33 healthy controls. Participants underwent visual and auditory oddball paradigm ERP assessments, neurological examinations using the Scale for the Assessment and Rating of Ataxia (SARA), and neuropsychological testing via the Stroop Color-Word Interference test. EEG signals were recorded at Cz and Pz electrode sites, with P300 latency and amplitude analyzed as indicators of attention, discrimination, and working memory. Statistical analyses included mixed-ANOVA, multiple regression, and receiver operating characteristic (ROC) analyses to determine group differences and correlations with clinical variables. Results indicated that SCA2 patients exhibited significantly increased P300 latencies and decreased amplitudes for both visual and auditory stimuli compared to controls. Preclinical carriers showed less severe but significant prolongations in P300 latencies, particularly for visual stimuli at Cz and auditory stimuli at Pz. Multiple regression analyses revealed that SARA scores significantly predicted visual P300 abnormalities in patients, linking cognitive electrophysiological deficits to motor severity. In preclinical carriers, the predicted time to ataxia onset significantly correlated with visual P300 latencies, suggesting that ERP abnormalities progress insidiously before clinical diagnosis. Additionally, P300 latencies correlated with Stroop test interference times in both patient and carrier groups, validating the ERP findings against behavioral cognitive measures. ROC analyses demonstrated high diagnostic accuracy for P300 latencies in identifying SCA2 patients. The study concludes that P300 ERP abnormalities are robust biomarkers for cognitive dysfunction in SCA2, appearing years before ataxia onset and correlating with disease progression. These findings provide psychophysiological evidence supporting cerebellar involvement in cognitive processes, likely due to disrupted cerebello-cerebral projections. The results suggest that P300 measures can serve as promising outcome metrics for monitoring disease progression and evaluating therapeutic efficacy in future trials targeting cognitive decline in SCA2 and potentially other polyglutamine disorders.

Provenance

The full processing record for this entry. Every stage of this paper's journey through the pipeline is logged — what ran, with which tool and model, how many attempts it took, and when it last completed.

Summary generated by qwen3.6-27b-prismaquant on 2026-06-26; verification: verified.

Topics

Ranked by relevance to this paper. Hover a topic for its definition.

• cognitive impairment