The neurobiology of cognitive disorders in temporal lobe epilepsy.

Department of Neurology, University of Wisconsin School of Medicine and Public Health, 600 North Highland Avenue, Madison, WI 53792, USA.
Nature Reviews Neurology (Impact Factor: 15.52). 02/2011; 7(3):154-64. DOI: 10.1038/nrneurol.2011.3
Source: PubMed

ABSTRACT Cognitive impairment, particularly memory disruption, is a major complicating feature of epilepsy. This Review will begin with a focus on the problem of memory impairment in temporal lobe epilepsy (TLE). We present a brief overview of anatomical substrates of memory disorders in TLE, followed by a discussion of how our understanding of these disorders has been improved by studying the outcomes of anterior temporal lobectomy. The clinical efforts made to predict which patients are at greatest risk of experiencing adverse cognitive outcomes following epilepsy surgery are also considered. Finally, we examine the vastly changing view of TLE, including findings demonstrating that anatomical abnormalities extend far outside the temporal lobe, and that cognitive impairments extend beyond memory function. Linkage between these distributed cognitive and anatomical abnormalities point to a new understanding of the anatomical architecture of cognitive impairment in epilepsy. Clarifying the origin of these cognitive and anatomical abnormalities, their progression over time and, most importantly, methods for protecting cognitive and brain health in epilepsy, present a challenge to neurologists.

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    PLoS ONE 12/2014; 9(12):e114606. · 3.53 Impact Factor
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    ABSTRACT: Patients with Temporal lobe epilepsy (TLE) frequently display cognitive comorbidity and can have widespread network abnormalities, which might affect a variety of cognitive and intellectual functions. As a result, refractory TLE seems to be associated with slow but ongoing cognitive deterioration. The case is of a 32 year old, right handed male, engineering graduate, diagnosed with TLE- right mesial, 12 years ago. A number of head injuries were caused due to the seizure present, which includes a fall from height of 12 feet in childhood. The neuropsychological tests administered were Gesell's Drawing Test, Mini Mental State Examination, PGI Memory Scale, Battery of Performance Tests of Intelligence, Verbal Adult Intelligence Scale, Hamilton Rating Scale for Depression, Bender Visual Motor Gestalt Test and Dysfunction Analysis Questionnaire. No impairment found on orientation; average cognitive functioning; above average attention and concentration, verbal working memory, visual and verbal memory; average practical ability, abstract ability, average verbal intellectual ability; superior ability on comprehension and average performance ability. Mild to moderate impairment on perceptuo-motor functioning and an evidence of depression were present. Patient showed high dysfunction in personal, social, vocational and cognitive areas. The study highlights that even despite chronic epilepsy, with a series of head injuries due to the seizures; an individual can still have average neuropsychological abilities. Holistic neuropsychological rehabilitation along with Vocational Retraining would go a long way in the functional independence of the patient. Neuropsychologists have a significant role in the assessment, treatment, and rehabilitation of people with epilepsy.
    Annals of Neurosciences 10/2014; 21(4):155-159.

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