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91.
In tetralogy of Fallot septal defect is usually large because of malalignment of outlet septum, restrictive defect has been reported rarely. We present a case of tetralogy of Fallot with accessory tricuspid leaflet tissue restricting ventricular septal defect. The report includes echocardiographic and catheter images of this rare presentation of tetralogy of Fallot.  相似文献   
92.
We studied the involvement of the parietal cortex in interpersonal body representation in a left parietal stroke patient. We used tasks assessing different types of body representations and localization of object parts. The patient performed normally on all tasks of body knowledge. However, she was unable to locate body parts on another person or on body representations. In contrast, she pointed correctly to the same body parts on herself or object representations. The data support the important role of the left parietal cortex in the transformation of intrinsic spatial coding of body parts localization in extrinsic body part coordinates.  相似文献   
93.
Posterior alien hand syndrome is a new addition to a poorly understood group of movement disorders. Historically, anatomical lesions causing uncontrolled limb movement and a feeling of foreignness were found to be located in the corpus callosum or frontal lobe. Recent case reports, however, demonstrate the typical symptoms of alien hand syndrome with lesions located in the parietal/occipital lobes. Disturbance of normal function in these regions tends to produce less complex motor activity, such as hand levitation, along with a sensory component characterized by feeling of estrangement. We discuss a patient who presented with unusual symptoms following an outpatient procedure and was found to have posterior alien hand syndrome.  相似文献   
94.
Abstract

A 41-year-old woman suffering from paretic neurosyphilis was treated successfully with high-dose penicillin. Detailed neuropsychological and neuroimaging studies were performed before and after treatment. The patient initially presented with presbyophrenia-like features of an amnesic-confabulatory state with a hypomanic mood. Pre-treatment neuropsychological examination revealed deficits in general intelligence, attention, memory, and frontal lobe executive function. Computed tomography (CT) and magnetic resonance imaging (MRI) demonstrated severe hippocampa/parahippocampal damage, in addition to fronto-temporal atrophy and ventricular dilatation. Immediately after treatment, she was no longer confabulatory or hypomanic, but remained densely amnesic. Neuropsychological examination at that time revealed a significant improvement in frontal lobe function, whereas her memory was still impaired. However, CT and MRI showed no interval change. Single-photon emission CT (SPECT) demonstrated a remarkable improvement in cerebral perfusion, but the Increase in frontal perfusion was relatively small. Seven months after treatment, clinical and neuropsychological examination revealed no evidence of memory impairment. Cerebral perfusion on SPECT in the frontal areas by this time had improved to normal. Positron emission tomography (PET), however, still showed patchy areas of hypoperfusion/hypometabolism. This study demonstrates the patient's stepwise clinical recovery following early antibiotic therapy and shows the dissociation of neuropsychological recovery and changes on SPECT and PET.  相似文献   
95.
Anarchic hand syndrome (AHS) is a rare disorder characterized by unwilled, but seemingly purposeful movements of the affected upper limb which are perceived by the patients not to be under their control. It often interferes with goal-directed movements and bimanual tasks. At present there is no effective method of treatment of AHS. We report here a case of AHS following resection of a frontal lobe tumor and describe its effects on the patient's functional activities. The patient used avoidance behavior and mental concentration to overcome the disabling effect of AHS. These strategies appear to be useful in the management of AHS.  相似文献   
96.
Recent case studies have suggested that emotion perception and emotional experience of music have independent cognitive processing. We report a patient who showed selective impairment of emotional experience only in listening to music, that is musical anhednia. A 71-year-old right-handed man developed an infarction in the right parietal lobe. He found himself unable to experience emotion in listening to music, even to which he had listened pleasantly before the illness. In neuropsychological assessments, his intellectual, memory, and constructional abilities were normal. Speech audiometry and recognition of environmental sounds were within normal limits. Neuromusicological assessments revealed no abnormality in the perception of elementary components of music, expression and emotion perception of music. Brain MRI identified the infarct lesion in the right inferior parietal lobule. These findings suggest that emotional experience of music could be selectively impaired without any disturbance of other musical, neuropsychological abilities. The right parietal lobe might participate in emotional experience in listening to music.  相似文献   
97.
We report the case of a 61-year-old female patient with intracranial bleeding in left parietal and parieto-temporal regions and a history of epilepsy and migraine. MR images showed lesions of the optic radiation, but primary visual cortical areas were intact. Perimetric testing revealed an incomplete right hemianopia. The patient claimed that visual percepts from her intact field were projected as “mirror images” into the hemianopic field. The illusory images were weak and sometimes difficult to detect, but focusing spatial attention on the “mirror” image increased its saliency. Drawings the patient made of her pseudo-hallucinations revealed that the illusions were lateral transpositions instead of mirror images of real objects. The illusions were tilted in clockwise direction and were never colored, although color discrimination was unimpaired in the patient's left hemifield. We quantified the characteristics of the pseudohallucinations in several experiments: The patient was asked to adjust the position, rotation angle, and size of a white test card in her blind field so that it corresponded with the illusory projection of a card of standard size and position that was presented in the intact field. The test card was compressed in horizontal size by 20% and positioned 17° visual angle to the right of the standard, shifted 1.5° upward or downward, and rotated in clockwise direction by 22.6° on average. Large objects in the intact field were projected incompletely into the blind area. Our patient's symptoms are similar to those reported in earlier case studies of visual allaesthesia. We hypothesize that the “mirror image” is induced by sparse input from contralesional V1 via the corpus callosum upstream of the lesion site and a lack of inhibition or hyperexcitability of ipsilesional early visual areas after deafferentation. The rotation of the illusions may be induced by the parietal lesions causing faulty co-ordinate computations, e.g., an inability to integrate visual and otholitic input.  相似文献   
98.
《Sleep medicine》2013,14(7):597-604
ObjectiveTo study the effects of antiepileptic treatment on sleep parameters and video-polysomnography (VPSG) seizures in nocturnal frontal lobe epilepsy (NFLE).MethodsTwenty patients with a clinical and VPSG diagnosis of NFLE (baseline polysomnography [PSG]) underwent a clinical follow-up and performed a second VPSG after effective antiepileptic treatment lasting for at least 6 months. Conventional sleep measures, cyclic alternating pattern (CAP) parameters, and objective VPSG seizures were assessed in NFLE patients before and after treatment and were compared with the results of 20 age- and gender-matched control subjects.ResultsAntiepileptic treatment determined a partial reduction of objective VPSG seizures of approximately 25% compared to baseline condition. Alterations of most conventional sleep measures recovered normal values, but nonrapid eye movement (NREM) sleep instability remained pathologically enhanced (CAP rate, +26% compared to controls) and was associated with persistence of daytime sleepiness.ConclusionsResidual epileptic events and high levels of unstable NREM sleep can define a sort of objective resistance of both seizures and disturbed arousal system to the therapeutic purpose of the antiepileptic drugs in NFLE. This finding could determine the need for new therapeutic options in this particular form of epilepsy.  相似文献   
99.
A large number of studies have demonstrated that depression patients have cognitive dysfunction. With recently developed brain functional imaging, studies have focused on changes in brain function to investigate cognitive changes. However, there is still controversy regarding abnormalities in brain functions or correlation between cognitive impairment and brain function changes. Thus, it is important to design an emotion-related task for research into brain function changes. We selected positive, neutral, and negative pictures from the International Affective Picture System. Patients with major depressive disorder were asked to judge emotion pictures. In addition, functional MRI was performed to synchronously record behavior data and imaging data. Results showed that the total correct rate for recognizing pictures was lower in patients compared with normal controls. Moreover, the consistency for recognizing pictures for depressed patients was worse than normal controls, and they frequently recognized positive pictures as negative pictures. The consistency for recognizing pictures was negatively correlated with the Hamilton Depression Rating Scale. Functional MRI suggested that the activation of some areas in the frontal lobe, temporal lobe, parietal lobe, limbic lobe, and cerebellum was enhanced, but that the activation of some areas in the frontal lobe, parietal lobe and occipital lobe was weakened while the patients were watching positive and neutral pictures compared with normal controls. The activation of some areas in the frontal lobe, temporal lobe, parietal lobe, and limbic lobe was enhanced, but the activation of some areas in the occipital lobe were weakened while the patients were watching the negative pictures compared with normal controls. These findings indicate that patients with major depressive disorder have negative cognitive disorder and extensive brain dysfunction. Thus, reduced activation of the occipital lobe may be an initiating factor for cognitive disorder in depressed patients.  相似文献   
100.
《Social neuroscience》2013,8(1):90-104
By nature, stereotypes require processes of categorization or semantic association, including social information about groups of people. There is empirical evidence that the anterior temporal lobe (ATL) processes domain‐general semantic information, and supports social knowledge. A recent study showed that inhibitory repetitive transcranial magnetic stimulation (rTMS) to the ATL reduced racial stereotypes on an implicit association test (IAT). However, it was not determined whether this was caused by changes to specific social, or general semantic processing, or both. The current study addresses these theoretical issues. The design investigated the effect of rTMS to the left or right ATL, or a sham stimulation, on a social IAT (gender stereotypes), a non-social IAT (living versus non-living associations), and a non-semantic control (Stroop) task. The results showed that low-frequency rTMS to both left and right ATL significantly reduced D-scores on the gender IAT compared to the sham group; however, there were no differences on the non-social IAT or the Stroop. The findings show the ATL has a role in mediating stereotypes, and the decrease of bias after stimulation could be due to weakening of social stereotypical associations either within the ATL or via a network of brain regions connected with the ATL.  相似文献   
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