Computational Modeling of Deficits in Attentional Networks in mild Traumatic Brain Injury: An Application in Neuropsychology

This work builds upon a model of performance for the Attentional Network Test (ANT) implemented in ACT-R 6.0 (Hussain & Wood, 2008; 2009) to simulate neglect conditions related to mild Traumatic Brain Injury (mTBI) and their effect on the attentional networks of alerting, orienting and executive control (cf. Posner & Fan, 2007). The model is evaluated against data sets for a human study of recovery in mTBI patients (Halterman, Langan, Drew, Rodriguez, Osternig, Chou & Donkelaar, 2006) and the models fit to data is assessed statistically. A description of the mTBI model is provided, outlining how the simulation of impairment is achieved using ACT-Rs1 symbolic and subsymbolic components. The process of data fitting within the constraints of model design supports the finding that alerting remains unimpaired in mTBI and indicates that orienting network impairment is mainly due to the affect of mTBI on the ability to disengage attention. The model data further indicates that modulation effects previously observed between attentional networks (Hussain & Wood, 2008; 2009) are preserved in the mTBI model, and do not reflect the impairment observed in orienting and executive control efficiency.