Predicting neurobehavioral patterns following anterior communicating artery aneurysm.
ABSTRACT This multiple case report presents two groups of survivors from aneurysms of the anterior communicating artery (ACoA); amnesic and non-amnesics, to examine the similarities and differences in neuropsychological profiles. All six patients were consecutive admissions to acute inpatient rehabilitation, and exhibited generally intact attention, concentration and intellectual ability. Confabulation and personality changes were observed only among the amnesic ACoA patients. However, difficulties in concept formation and perseverative responding was observed in all subjects. A neurobehavioral hypothesis addressing the underlying mechanism of the main features of the "ACoA syndrome" is presented.
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ABSTRACT: A 57-year-old man suffered severe amnesia and disorientation, accompanied by content-specific confabulation, due to an alcoholic Wernicke-Korsakoff syndrome. For months, he was deeply concerned about a single obligation that he thought he had to respond to, but which he had already assumed 20 years previously. This monothematic, prospective confabulation was associated with failures of reality filtering as previously documented in behaviorally spontaneous confabulation and disorientation: the patient failed to suppress the interference of currently irrelevant memories and to abandon anticipations that were no longer valid (impaired extinction capacity). Magnetic resonance imaging showed damage to the mamillary bodies and the dorsomedial thalamic nucleus. Positron emission tomography (FDG-PET) showed extended orbitofrontal hypometabolism. We suggest that isolated prospective confabulation shares the core feature (acts and thoughts based on currently irrelevant memory), mechanism (failure of reality filtering), and anatomical basis (orbitofrontal dysfunction) with behaviorally spontaneous confabulations.Neurocase 04/2012; · 1.38 Impact Factor
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ABSTRACT: A biophysical model of a neocortical microcircuit system is formulated and employed in studies of neuromodulatory control of dynamics and function. The model is based on recent observations of reciprocal connections between pyramidal cells and inhibitory interneurons and incorporates a new type of activity-dependent short-term depression of synaptic couplings recently observed. The model neurons are of a low-dimensional type also accounting for neuronal adaptation, i.e. the coupling between neuronal activity and excitability, which can be regulated by various neuromodulators in the brain. The results obtained demonstrate a capacity for neuromodulatory control of dynamical mode linked to functional mode. The functional aspects considered refer to the observed resolution of multiple objects in working memory as well as the binding of different features for the perception of an object. The effects of neuromodulators displayed by the model are in accordance with many observations on neuromodulatory influence on cognitive functions and brain disorders.Journal of Biological Physics 09/2004; 30(3):261-84. · 1.15 Impact Factor
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ABSTRACT: Main aim: The article contains a description of cognitive functioning of two children after surgery of brain aneurysm. Vascular malformations of the brain in children are very rare in clinical practice, so it is of great importance to investigate the long-term neuropsychological consequences of aneurysmal subarachnoid haemorrhage, including social and emotional functioning of these children. Material and method: Two children were neuropsychologically investigated, a thirteen-year old boy and a sixteen-year old girl. In both cases the aneurysm was located in the left parietal lobe, parietal-occipital artery. In the first case the investigation took place two years after the surgery, and in the second case four years after the surgery. In the neuropsychological investigation several tools were used including: the Wechsler Intelligence Scale, and some experimental methods from the Łucki Book for investigating the cognitive functioning of patients with organic brain damage. An interview with the parents of the children was also undertaken. Results: Significant neuropsychological deficits were observed in two described patients which negatively influence the educational as well as social functioning of the children. In both cases there were problems with memory functioning and learning new material – the most important cognitive ability which helps to effectively adapt to new situations. Conclusions: Early finding of neuropsychological deficits in children after aneurysmal subarachnoid haemorrhage can provide an effective neurorehabilitation of some cognitive functions and help these children to adapt to new situations of the illness.Neuropsychiatria i Neuropsychologia 01/2009; 4(1):36-42.