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BACKGROUND: Focal thalamic lesions have been associated with a variety of involuntary movements such as tremor, dystonia, and chorea-ballism. METHODS: We describe a patient with severe hyperkinesias of the right arm secondary to a thalamic infarction in the left postero-ventral region of the thalamus. RESULTS: The dystonia and tremor of the right upper limb were subsequently controlled with another surgical lesion of the ventralis intermedius nucleus of the thalamus. CONCLUSION: This observation suggests that ablative surgery might be applied to treat a movement disorder induced by the lesion of the same nucleus, which in addition lead to interesting pathophysiological conjectures.

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OBJECTIVE: To study the Zolpidem arousing effect in persistent vegetative state (PVS) patients combining clinical evaluation, autonomic assessment by heart rate variability (HRV), and EEG records. METHODS: We studied a group of 8 PVS patients and other 8 healthy control subjects, matched by age and gender. The patients and controls received drug or placebo in two experimental sessions, separated by 10-14 days. The first 30 minutes of the session were considered the basal record, and then Zolpidem was administered. All participants were evaluated clinically, by EEG, and by HRV during the basal record, and for 90 minutes after drug intake. RESULTS: We found in all patients, time-related arousing signs after Zolpidem intake: behavioral (yawns and hiccups), activation of EEG cortical activity, and a vagolytic chronotropic effect without a significant increment of the vasomotor sympathetic tone. CONCLUSIONS: We demonstrated time-related arousing signs after Zolpidem intake. We discussed possible mechanisms to explain these patho-physiological findings regarding EEG cortical activation and an autonomic vagolytic drug effect. As this autonomic imbalance might induce cardiocirculatory complications, which we didn't find in any of our patients, we suggest developing future trials under control of physiological indices by bedside monitoring. However, considering that this arousing Zolpidem effect might be certainly related to brain function improvement, it should be particularly considered for the development of new neuro-rehabilitation programs in PVS cases. According to the literature review, we claim that this is the first report about the vagolitic effect of Zolpidem in PVS cases.

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INTRODUCTION: Zolpidem is a non-benzodiazepine drug used for the therapy of insomnia, which has selectivity for stimulating the effect of GABA-A receptors. Recently, a paradoxical arousing effect of zolpidem in patients with severe brain damage has been repeatedly reported. METHODS: A placebo-controlled magnetic resonance study was conducted to evaluate its effect on BOLD and metabolites spectral signals in a patient with severe brain injuries and an age-matched healthy volunteer. A multi-modal analysis was used to assess aspects in the pharmacologically-induced changes in the resting-state brain metabolism. RESULTS: A significantly increased BOLD signal was transiently localized in the left frontal cortices, bilateral anterior cingulated areas, left thalamus and right head of the caudate nucleus. The healthy subject showed a deactivation of the frontal, parietal and temporal cortices. BOLD signal changes were found to significantly correlate with concentrations of extravascular metabolites in the left frontal cortex. It is discussed that, when zolpidem attaches to modified GABA receptors of neurodormant brain cells, brain activation is induced. This might explain the significant correlations of BOLD signal changes and proton-MRS metabolites in this patient after zolpidem. CONCLUSION: It was concluded that proton-MRS and BOLD signal assessment could be used to study zolpidem-induced metabolic modulation in a resting state.

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The term persistent vegetative state (PVS) refers to the only circumstance in which an apparent dissociation of both components of consciousness is found, characterized by preservation of wakefulness with an apparent loss of awareness. Several authors have recently demonstrated by functional neuroimaging studies that a small subset of unresponsive "vegetative" patients may show unambiguous signs of consciousness and command following that is inaccessible to clinical examination at the bedside. The term "estado vegetativo" used in Spanish to describe the PVS syndrome by physicians came from the English-Spanish translation. The Spanish term "vegetativo" is related to unconscious vital functions, and "vegetal" is relative to plants. According to our experience, when a physician informs to patients' relatives that his/her family member's diagnosis is a "estado vegetativo", they understand the he/she is no more a human being, that there is no hope of recovery. The European Task Force on Disorders of Consciousness has recently proposed a new term, unresponsive wakefulness syndrome (UWS), to assist society in avoiding the depreciatory term vegetative state. Our group has embraced the use of the new term UWS and might suggest that we change our concept and use of the term MCS to minimally responsive wakefulness state (MRWS), or minimally aware wakefulness state (MAWS). Medical terms must be current and avoid any pejorative description of patients, which will promote our abilities to serve humankind and challenge neuroscientists to offer society new and realistic hopes for neurorehabilitation.

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The Cuban Group for Study of Disorders of Consciousness is developing several research protocols to search for possible preservation of residual brain and autonomic functions in cases of persistent vegetative and minimally conscious states. We present examples showing the importance of 3D anatomic reconstruction of brain structures and MRI tractography for assessing white matter connectivity. We also present results of use of proton magnetic resonance spectroscopy technique to follow up cognitive recovery in persistent vegetative state patients transitioning to minimally conscious state. We have demonstrated recognition of a mother's voice with emotional content after zolpidem administration, indicating high-level residual linguistic processing and brain activation despite the patient's apparent inability to communicate. Hence we differ with current thinking that, by definition, subjects in persistent vegetative state are isolated from the outside world and cannot experience pain and suffering. We also consider "vegetative state" a pejorative term that should be replaced. KEYWORDS Persistent vegetative state, minimally conscious state, consciousness disorders, magnetic resonance imaging, electroencephalography, heart rate variability.

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BACKGROUND: We report a 15 year-old girl with sickle cell disease, who developed important cognitive impairment due to multiple strokes, and who had been diagnosed with PVS. Nonetheless, when she was later admitted to our Institute, according to the presence of inconsistent but clearly demonstrable behavioral evidence of consciousness awareness, we changed our diagnosis to MCS. METHODS: This patient was studied by T1 MRI images, co-registration of fractional anisotropy (FA), and SPECT with MRI. RESULTS: Brain structures were mainly preserved in posterior areas of both cerebral hemispheres, although small tissue islands were present in both frontal lobes, mainly preserved in the right one. SPECT showed CBF preservation in posterior brain regions and in the cerebellum, and in those frontal small islands of tissue lateralized to the right frontal lobe; meanwhile FA showed preservation of anatomical connectivity among posterior and frontal brain regions. These remaining cortical regions are also connected with the thalami. CONCLUSION: These results showing connectivity among posterior and frontal cortical and probably with other subcortical regions, and CBF preservation in these areas, might explain the recovery of minimum awareness despite huge anatomical brain lesions.

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