Epileptic monocular nystagmus and ictal diplopia as cortical and subcortical dysfunction

AbstractWe present the case of a patient with ictal monocular nystagmus and ictal diplopia who became seizure-free after resection of a right frontal focal cortical dysplasia (FCD), type 2B. Interictal neuroophthalmological examination showed several beats of a monocular nystagmus and a spasm of the contralateral eye. An exclusively ictal monocular epileptic nystagmus could be an argument for an exclusively cortical involvement in monocular eye movement control. The interictal findings in our patient, however, argue for an irregular ictal activation of both the cortical frontal eye field and the brainstem

Reorganization of memory functions after human temporal lobe damage

Jokeit H, Ebner A, Holthausen H, Markowitsch HJ, Tuxhorn I. Reorganization of memory functions after human temporal lobe damage. Neuroreport. 1996;7(10):1627-1630.HEMISPHERIC (re-)organization of episodic memory functions after temporal lobe damage (TLD) was investigated by the intracarotid amobarbital procedure in patients suffering temporal lobe epilepsy. Memory of the speech-dominant left hemisphere was intact after right-sided TLD independent of the age at manifestation. In contrast, the right hemisphere mediated memory well only after early left-sided TLD. These findings suggest a predisposition of the speech-dominant left hemisphere for the encoding of episodic memory, and indicate that for left-sided TLD the right hemisphere may compensate memory encoding sufficiently only if the damage occurred within a critical period in childhood

Presurgical language fMRI activation correlates with postsurgical verbal memory decline in left-sided temporal lobe epilepsy

Labudda K, Mertens M, Aengenendt J, Ebner A, Woermann FG. Presurgical language fMRI activation correlates with postsurgical verbal memory decline in left-sided temporal lobe epilepsy. Epilepsy Research. 2010;92(2-3):258-261.We analysed the association of presurgical language fMRI activations and postsurgical verbal memory changes in 16 left-sided mesial temporal lobe epilepsy patients with initially intact memory. Patients with severe verbal memory decline after surgery (n=9) had stronger presurgical fMRI activations within the left posterior temporal lobe, compared to those with no decline (n=7). Language fMRI activation may predict verbal memory outcome, even in patients with a high risk of postsurgical memory deterioration. (C) 2010 Elsevier B.V. All rights reserved

Alterations of decision making and underlying neural correlates after resection of a mediofrontal cortical dysplasia: A single case study

Labudda K, Brand M, Mertens M, Ebner A, Markowitsch HJ, Woermann FG. Alterations of decision making and underlying neural correlates after resection of a mediofrontal cortical dysplasia: A single case study. NEUROCASE. 2010;16(1):59-73.We investigated the impact of a congenital prefrontal lesion and its resection on decision making under risk and under ambiguity in a patient with right mediofrontal cortical dysplasia. Both kinds of decision making are normally associated with the medial prefrontal cortex. We additionally studied pre- and postsurgical fMRI activations when processing information relevant for risky decision making. Results indicate selective impairments of ambiguous decision making pre- and postsurgically. Decision making under risk was intact. In contrast to healthy subjects the patient exhibited no activation within the dysplastic anterior cingulate cortex but left-sided orbitofrontal activation on the fMRI task suggesting early reorganization processes