Cognitive disconnective syndrome by single strategic strokes in vascular dementia Maria Elisa de Oliveira Lanna a, d, ⁎, Carlos Eduardo O. Alves a , Felipe Kenji Sudo a , Gilberto Alves a , Letice Valente a , Denise Madeira Moreira b, c , José Luiz Sá Cavalcanti d , Eliasz Engelhardt a, d a Centro para Doença de Alzheimer, Instituto de Psiquiatria, Universidade Federal do Rio de Janeiro (CDA/IPUB/UFRJ), Rio de Janeiro RJ, Brazil b Setor de Neuroimagem, Instituto de Neurologia Deolindo Couto (INDC/UFRJ), Rio de Janeiro RJ, Brazil c Hospital Pró-Cardíaco, Rio de Janeiro RJ, Brazil d Setor de Neurologia Cognitiva e do Comportamento, Instituto de Neurologia Deolindo Couto (INDC/UFRJ), Rio de Janeiro RJ, Brazil abstract article info Article history: Received 31 January 2012 Received in revised form 4 August 2012 Accepted 7 August 2012 Available online 28 August 2012 Keywords: Strategic regions Stroke Eloquent circuits Cognitive impairment Behavioral disorder Vascular dementia Strategic regions correspond to associative, limbic and paralimbic structures and related circuits, that underpin cognitive/behavioral functions. Strokes in these eloquent sites produce pictures of vascular dementia with syndromic features due to specific site lesion and/or interruption of their interconnections. This study aims at analysing subcortical strategic strokes that express similar cognitive/behavioral elements, by sharing common pathways. Patients (n = 6) who attended in specialized ambulatory, were submitted to neuropsychological and neuroimaging assessments through MRI (GE Signa Horizon 1.5T) and brain SPECT (Millennium MG, ECD [TC-99m]). Stroke locations and respective main symptoms were: 1. anteromedian thalamus [L]: anterograde and retrograde amnesia (ARA), expression aphasia (EA), executive dysfunction (ED), apathy, and depression; 2. anterior thalamus [R]: ARA, inattention, apathy, and aggressiveness; 3. dorsomedian thalamus [L]: inattention, ED, anosognosia, and aggressiveness; 4. central paramedian thalamus [R]: EA, visual perception deficits (VPD), ED, infantility, and personality disorder; 5. caudate nucleus (ventral-head) [L]: VPD, ED, delirium, visual hallucinations, and personality disorder; and 6. anterior capsule [L]: VPD, ED, apathy, and depression. Vascular strategic syndromes connote the predominantly impaired cognitive/behavioral symptom of each site. Temporal and frontal disconnection symptoms were produced by disrupted MTT/hippocampal and IML/amygdala circuits expressing amnesic syndrome associated with heterogeneous dysexecutive syndrome, in all the cases, by disrupting frontal–basal ganglia–thalamus– cortical net, in three different levels of their pathway. © 2012 Elsevier B.V. All rights reserved. 1. Introduction The strokes that occur in critical regions of the cognitive/behavioral circuits are denominated strategics [1,2] for producing pictures with clinical expression of vascular dementia (VD) of variable intensity [3–7] dependent on the strategic site involved [1,2]. The anatomical substrate related to strategic infarcts includes the associative, limbic and paralimbic cortical areas, established under Mesulam [8,9], in the map of Brodmann, comprising the superior temporal gyrus, angular gyrus and prefrontal regions, the hippocampal formation, the parahippocampal gyrus and the cingulate gyrus as well as subcortical structures such as thalamus (anterior, dorsomedial, later- odorsal, lateroposterior and part of the pulvinar nuclei), caudate nucleus (head and anterior body), basal forebrain (amygdala-claustro region, amygdala and septal area); it also includes the bundles of white matter that connect these structures by association and projection path. It forms the circuit network associative, limbic and paralimbic, and performs the function of integrating the cognitive and psychological/behavioral information processed in these circuits [10–15]. The mechanism involved in the production of demential syndrome by the vascular insult, comprises the direct injury and disconnection of the structures and networks listed above, producing a functional disconnection of systems [6,16–18]. There are numerous connections involving this network, some of them could be individualized as the Papez [10] and Mishkin [11] circuits which represent part of the limbic and paralimbic connections, and come from different regions of the hippocampal region. The limbic circuit of Papez that stems from the subiculum and via fornix, is addressed to the mammillary bodies and this for the anterior thalamic nuclei via mammillothalamic tract (MTT), and projects to the anterior cingulate cortex [10]. The paralimbic circuit of Mishkin, originates from the basolateral amygdala of its division of efferent fibers, and go through the inferior thalamic peduncle to the dorsomedial nucleus of the thalamus via internal medullary lamina (IML), then project to the prefrontal cortex, dorsolateral and orbitofrontal cortices [11]. These circuits seem to finish their connections into three distinct subregions of the prefrontal cortex, however the information provided, Journal of the Neurological Sciences 322 (2012) 176–183 ⁎ Corresponding author at: Setor de Neurologia Cognitiva e do Comportamento, INDC/UFRJ. Av. Venceslau Brás, 95, Campus Praia Vermelha, Cep: 22290‐140, Rio de Janeiro RJ, Brazil. Tel.: +55 21 2540 0659; fax: +55 21 2295 9794. E-mail address: deo_lanna@terra.com.br (M.E.O. Lanna). 0022-510X/$ – see front matter © 2012 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.jns.2012.08.004 Contents lists available at SciVerse ScienceDirect Journal of the Neurological Sciences journal homepage: www.elsevier.com/locate/jns