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Deep brain stimulation is generally a safe and effective method of alleviating motor impairment in advanced-stage Parkinson's disease patients. However, adverse events of surgery have been noted, such as hemorrhage, infection, seizures, and device failure. In this report, we describe 2 cases of the unusual adverse event of ischemia associated with subthalamic nucleus stimulator implantation. We present the intraoperative neurological symptoms, microelectrode recording data, imaging findings, and other correlated events. In the first case, the clinical effects of ischemia were evident intraoperatively and coincided with silence during microelectrode recording from the ischemic region. In the second case, the timing of the ischemic event could not be determined precisely but also was associated with a difficult mapping. Subcortical ischemia may be an underrecognized event that confounds neurophysiological mapping of deep brain structures and affects clinical outcomes., ((c) 2006 Movement Disorder Society.)

We report five cases with caudate infarction due to Heubner's recurring artery occlusion, in which we conducted detailed memory examinations in terms of explicit memory and implicit memory. We performed the auditory verbal learning test as explicit memory tasks, and motor and cognitive procedural memory tasks, developed by Komori, as implicit memory tasks. Comparing normal control subjects with patients with left caudate infarction due to Heubner's recurring artery occlusion demonstrated lower scores on both declarative and motor procedural memory tasks. These results suggest that the left caudate nucleus may be related with both declarative memory and procedural memory.

Adults have difficulty discriminating nonnative phonetic contrasts, but under certain circumstances training can lead to improvement in this ability. Despite the ubiquitous use of performance feedback in training paradigms in this and many other domains, the mechanisms by which feedback affects learning are not well understood. In this event-related functional magnetic resonance imaging study, we examined how performance feedback is processed during perceptual learning. Thirteen Japanese speakers for whom the English phonemes [r] and [l] were nondistinct performed an identification task of the words "road" and "load" that has been shown to be effective in inducing learning only when performance feedback is present. Each subject performed alternating runs of training with and without feedback, followed by performance of a card-guessing task with monetary reward and punishment outcomes. We found that the caudate nucleus was more robustly activated bilaterally when performing the perceptual identification task with feedback than without feedback, and the right caudate nucleus also showed a differential response to positive and negative feedback. Moreover, using a within-subjects design, we found that the caudate nucleus also showed a similar activation pattern to monetary reward and punishment outcomes in the card-guessing task. These results demonstrate that the caudate responds to positive and negative feedback during learning in a manner analogous to its processing of extrinsic affective reinforcers and indicate that this region may be a critical moderator of the influence of feedback on learning. These findings impact our broader understanding of the mechanisms underlying nondeclarative learning and language acquisition.

Objective: To evaluate the effects of HIV-associated neurocognitive impairment on caudate blood flow and volume., Methods: The authors performed continuous arterial spin labeled MRI on 42 HIV+ patients (23 subsyndromic and 19 HIV neurosymptomatic) on highly active antiretroviral therapy and 17 seronegative controls. They compared caudate blood flow and volume among groups., Results: A stepwise decrease in both caudate blood flow and volume was observed with increasing HIV-associated neurocognitive impairment. Compared with seronegative controls, baseline caudate blood flow was reduced in HIV+ neurosymptomatic patients (p = 0.001) with a similar decreasing trend for subsyndromic HIV+ patients (p = 0.070). Differences in caudate volume were observed only for neurosymptomatic HIV+ patients compared with controls (p = 0.010). A Jonckheere-Terpstra test for trends was significant for both caudate blood flow and volume for each of the three subgroups. Pearson product moment correlation coefficients were not significant between caudate blood flow and volume for each group., Conclusions: Decreasing trends in caudate blood flow and volume were associated with significantly increasing HIV-associated neurocognitive impairment (HNCI), with the greatest decreases observed for more severely impaired patients. However, reductions in caudate blood flow and volume were poorly correlated. Changes in residual caudate blood flow may act as a surrogate biomarker for classifying the degree of HNCI.

Purpose: The aim of our study was to assess the regional cerebral blood flow (rCBF) of basal ganglia and thalami in patients with Parkinson's disease (PD) using perfusion-weighted magnetic resonance imaging (PW-MRI)., Material and Methods: Twenty subjects affected by idiopathic PD according to the United Kingdom Brain Bank criteria were enrolled in the study. Twenty normal subjects matched for age and gender were included as controls. After 20-day therapy withdrawal, the PD patients underwent PW-MRI. The rCBF was calculated both in patients and in controls. The regions of interest were manually positioned on rCBF maps over the caudate nucleus, the putamen, the external and internal globus pallidus, and over the ventrolateral nucleus of the thalamus. Data were normalised with those obtained from parieto-occipital white matter (POWM). Statistical analysis was performed using a parametric ANOVA test., Results: Patients showed a significant (p<0.01) interhemispheric asymmetry; rCBF values were higher on the more severely affected side. Controls showed no interhemispheric asymmetry., Conclusion: Our study suggests that PW-MRI is a valuable tool for assessing haemodynamic changes in PD patients. Haemodynamic change pattern may be useful in the early diagnosis of PD.

Objective: Recent studies of functional brain imaging have shown the involvement of the basal ganglia in executive processes such as planning and set-shifting. However, the specific contributions of the striatum in those processes remain unknown. This study aimed to test the hypothesis that the caudate nucleus is primarily involved in the preparation of a novel action and not in set-shifting per se., Methods: In the present event-related functional magnetic resonance imaging (fMRI) study, a new task was developed that permitted, for the first time, to distinguish between shifts in classification when the rule is implicitly given by the task from shifts that require cognitive comparison and planning., Results: Significantly increased activity in the caudate nucleus and the putamen was observed only in conditions in which cognitive planning was required to perform a set-shift, whereas significant activation was seen in the subthalamic nucleus (another region of the basal ganglia) in all shifting conditions whether or not planning was required., Interpretation: We suggest that the caudate nucleus and the putamen are particularly important, respectively, in the planning and the execution of a self-generated novel action, whereas the subthalamic nucleus may be required when a new motor program is solicited independently of the choice of strategy.

This study employed functional magnetic resonance imaging to examine the functional neuroanatomy of the hippocampus and head of the caudate nucleus during 2 different types of memory tasks in a sample of 9 early adolescent children who were born preterm (neonatal intensive care unit [NICU] sample) and a group of 9 age-matched control children who were born at term. The investigation employed delayed match to sample (DMS), delayed nonmatch to sample (DNMS), and spatial memory span tasks, as well as 2 analogous perceptuomotor tasks that placed no demands on memory. The general question examined was whether preterm children show different levels of hippocampal and caudate activation during these tasks when compared to children born at term. The findings indicated that the 2 groups did not differ in functional activation of the hippocampus during the DMS and DNMS tasks. During the encoding phase of the spatial memory span task, the DMS perceptuomotor task, and the spatial memory span perceptuomotor task, the NICU sample showed greater activation change in the right caudate nucleus, and less right caudate activation change during the test phase. During the spatial span perceptuomotor task, the preterm group showed reduced activation change in the left caudate nucleus during both the encoding and test phase. Also, during the DMS perceptuomotor task, the NICU group showed increased activation change in the left caudate nucleus during encoding and decreased activation change at test. The implications of these findings for understanding the functional neuroanatomy of memory deficits are discussed, as is the potential for distinguishing the effects of neural plasticity from those of typical brain maturational processes.

Purpose: Previous cerebral blood flow and glucose metabolism studies suggest that the basal ganglia or thalamus is involved in the pathogenesis of paroxysmal kinesigenic choreoathetosis (PKC). However, the underlying cerebral abnormalities in idiopathic PKC have not been elucidated. To localise cerebral perfusion abnormalities in PKC, we performed interictal brain perfusion 99mTc-ethylcysteinate dimer (ECD) single-photon emission computed tomography (SPECT) in PKC patients and in normal controls., Methods: Sixteen patients with idiopathic PKC and 18 age- and sex-matched normal controls were included. The patients were de novo diagnosed as having PKC, or had not taken medication for at least 3 months; none of them had structural abnormalities on MRI. Patients had a history of PKC attacks of a duration not exceeding 5 min and starting either on one side or on both sides of the body. These attacks were always induced by a sudden initiation of voluntary movement. PKC attacks were recorded in a hospital after being induced by neurology staff in 13 of the 16 patients. Interictal brain perfusion 99mTc-ECD SPECT was performed in all 16 patients and 18 normal controls. Differences between the cerebral perfusion in the PKC group and the normal control group were tested by statistical parametric mapping. Student's t test was used for inter-group comparisons., Results: Compared with normal controls, patients with idiopathic PKC showed interictal hypoperfusion in the posterior regions of the bilateral caudate nuclei (false discovery rate-corrected P<0.001 with a small volume correction)., Conclusion: This study showed that cerebral perfusion abnormality of bilateral caudate nuclei is present in idiopathic PKC.

Fatal Familial Insomnia (FFI) is characterized by loss of sleep, oneiric stupor with autonomic/motor hyperactivity and somato-motor abnormalities (pyramidal signs, myoclonus, dysarthria/dysphagia, ataxia). Positon emission tomography (PET) disclosed thalamic hypometabolism and milder involvement of the cortex; neuropathology severe neuronal loss in the thalamic nuclei variably affecting the caudate, gyrus cinguli and fronto-temporal cortices. Genetic analysis disclosed a mutation in the PRNP gene and FFI was transmitted to experimental animals, thus classifying FFI within the prion diseases. Rare Sporadic Fatal Insomnia (SFI) cases occur without PRNP mutation but with features similar to FFI. FFI represents a model disease for the study of sleep-wake regulation: (I) the profound thalamic hypometabolism/atrophy associated with lack of sleep spindles and delta sleep implicate the thalamus in the origin of slow wave sleep (SWS); (II) loss of SWS is associated with marked autonomic and motor hyperactivity; termed 'agrypnia excitata', this association has been proposed as a useful clinical concept representative of thalamo-limbic dysfunction; (III) lack of SWS occurs with substantial preservation of stage 1 NREM sleep, implying that the latter has mechanisms different from SWS and unaffected by thalamic atrophy; accordingly, conflating stage 1 NREM with SWS into NREM sleep is inappropriate.

We studied time-related changes in the blood oxygenation-level-dependent signal during a time reproduction task. Nine healthy study participants retained and reproduced stimuli of varying durations in the multi-second range. During the encoding phase of the task, activity in the left dorsolateral prefrontal cortex inversely correlated with the interval duration, while an adjacent region in the dorsolateral prefrontal cortex showed positive correlation with duration in the reproduction phase. Cumulative signal increase during the reproduction phase, as found in the primary motor and supplementary motor areas, may also reflect the time-sensitive behavior. Signal accumulation in the right caudate nucleus is in agreement with presumed role of basal ganglia in time perception. These results support the 'time accumulator' hypothesis.

The diagnosis of probable Creutzfeldt-Jakob disease (CJD) requires compatible clinical manifestations, typical electroencephalographical findings, and 14.3.3 protein positive in cerebrospinal fluid. Actually, MRI findings are not necessary, but they may support this diagnosis. The authors report a patient with definitive diagnosis of CJD who showed in a first MRI study performed two years before the clinical onset of the disease the same hyperintensities in caudate nuclei that were found in the last MRI. The authors think that these findings could be useful in detecting asymptomatic patients who need more extensive study and following.

Background: Scarce information about the anatomy of the subependymal arteries (SEAs) is present in the scientific literature., Methods: Twenty cerebral hemispheres with injected arteries were microdissected, and the magnetic resonance imaging scans of 100 patients with lacunar infarcts were examined., Results: The SEAs were found to range in diameter from 40 to 490 microm (mean, 149 microm) and in number between 3 and 12 (average, 5.2). Of these, numbers from 1 to 3 originated from the anterior choroidal artery (AChA), between 1 and 10 from the lateral posterior choroidal artery (LPChA), 1 from the medial posterior choroidal artery (MPChA), and 1 from the internal carotid artery. The SEAs most often arose from the choroidal branches (90%) and less frequently from the thalamic (30%), caudate (35%), or thalamocaudate twigs (20%). The SEAs of the AChA supplied the walls of the temporal horn (100%), the occipital horn (85%), and the atrium (35%). Those of the LPChA perfused the walls of the occipital horn (15%), the atrium (65%), the body of the ventricle (100%), and partially the frontal horn. The SEAs of the MPChA partially nourished the body and the frontal horn (10%). The SEAs may also occasionally supply the caudate nucleus (20%) and the stria terminalis. The anastomoses involving the SEAs were absent. In spite of this, ischemia in the territory of a single SEA was noticed in only 1% of our patients., Conclusions: The SEAs are tiny vessels that supply the walls of the lateral ventricle, as well as the caudate nucleus and the stria terminalis occasionally. The obtained anatomic data can have important neurosurgical implications in intraventricular operations.

Using a multiround version of an economic exchange (trust game), we report that reciprocity expressed by one player strongly predicts future trust expressed by their partner-a behavioral finding mirrored by neural responses in the dorsal striatum. Here, analyses within and between brains revealed two signals-one encoded by response magnitude, and the other by response timing. Response magnitude correlated with the "intention to trust" on the next play of the game, and the peak of these "intention to trust" responses shifted its time of occurrence by 14 seconds as player reputations developed. This temporal transfer resembles a similar shift of reward prediction errors common to reinforcement learning models, but in the context of a social exchange. These data extend previous model-based functional magnetic resonance imaging studies into the social domain and broaden our view of the spectrum of functions implemented by the dorsal striatum.

The caudate nucleus is commonly active when learning relationships between stimuli and responses or categories. Previous research has not differentiated between the contributions to learning in the caudate and its contributions to executive functions such as feedback processing. We used event-related functional magnetic resonance imaging while participants learned to categorize visual stimuli as predicting "rain" or "sun." In each trial, participants viewed a stimulus, indicated their prediction via a button press, and then received feedback. Conditions were defined on the bases of stimulus-outcome contingency (deterministic, probabilistic, and random) and feedback (negative and positive). A region of interest analysis was used to examine activity in the head of the caudate, body/tail of the caudate, and putamen. Activity associated with successful learning was localized in the body and tail of the caudate and putamen; this activity increased as the stimulus-outcome contingencies were learned. In contrast, activity in the head of the caudate and ventral striatum was associated most strongly with processing feedback and decreased across trials. The left superior frontal gyrus was more active for deterministic than probabilistic stimuli; conversely, extrastriate visual areas were more active for probabilistic than deterministic stimuli. Overall, hippocampal activity was associated with receiving positive feedback but not with correct classification. Successful learning correlated positively with activity in the body and tail of the caudate nucleus and negatively with activity in the hippocampus.

Spreading depression-like peri-infarct depolarizations not only characterize but also worsen penumbra conditions in cortical border zones of experimental focal ischemia. We intended to investigate the relevance of ischemic depolarization in subcortical regions of ischemic territories. Calomel electrodes measured DC potentials simultaneously in the lateral and medial portions of the caudate nucleus (CN) of 11 anesthetized cats after permanent occlusion of the middle cerebral artery. Additionally, platinum electrodes measured cerebral blood flow (CBF) in the CN, and laser Doppler probes CBF in the cortex. Depolarizations (negative DC shifts >10 mV) were obtained in 10 of 11 cats. Further differentiation revealed that short-lasting spreading depression-like depolarizations (SDs; 5 of 10 cats: 5.24 +/- 1.22 min total duration; 23.3 +/- 4.2 mV amplitude) were predominantly found in medial and longer depolarizations (LDs; 4 of 10 cats: 64.7 +/- 47.5 min; 25.0 +/- 11.3 mV) in the lateral CN. Terminal depolarizations (TDs; 6 of 10 cats; without repolarization) occurred immediately after occlusion or at later stages, being then accompanied by elevations of intracranial pressure presumably inducing secondary CBF reduction. CBF tended to be lower in regions with TDs (33.3 +/- 29.9% of control) and LDs (37.3 +/- 22.8%) than in regions with SDs (51.5 +/- 48.0%). We conclude that in focal ischemia, transient peri-infarct depolarizations emerge not only in cortical but also in striatal gray matter, thereby demonstrating the existence of subcortical zones of ischemic penumbra. The generation of these ischemic depolarizations is a multifocal process possibly linked to brain swelling and intracranial pressure rise in the later course of focal ischemia, and therefore a relevant correlate of progressively worsening conditions.

Clinical and neuropsychological study of 28 patients with arteriovenous malformations (AVM) of the caudate nucleus and 36 patients with AVM of the thalamus has been conducted. After surgical removal of the caudate nucleus, speech disturbances developed in 4 out of 8 patients with left-side AVM and in 1 patient, a converted left-hander, with right-side AVM. All 5 patients had mild speech disturbances, which differed by character in dependence of the AVM location. In case of AVM location in the head of the caudate nucleus, the speech disturbances were represented by perseverations and were similar to those caused by the lesion in the Broca area. In case of the caudate nucleus lesion, naming was mildly affected that resembled temporal aphasia. After surgical removal of AVM in the left thalamus in 9 patients, complex and rather stable speech disturbances developed in 7 cases. They were featured by the signs of frontal and temporal aphasias, i.e. there were perseverations and disturbances of naming, auditory and speech memory. The peculiarities of speech disturbances in lesions of the caudate nucleus and the thalamus were well explained by their anatomic and functional correlations with different regions of brain speech cortex. Speech disturbances in various subcortical lesions are reviewed. In the authors' opinion, subcortical aphasias do not have any particular character but include the same factors in different combinations as cortical ones that is determined by the presence of common functional systems for speech support which comprise cortical and subcortical patterns.

Recent neurobiological models of obsessive-compulsive disorder (OCD) posit that a dysfunction in orbitofrontal-subcortical circuitry underlies the etiology of this disorder. Much of the empirical support for these theories comes from studies using neuroimaging techniques to compare brain activity in OCD patients with that in non-OCD controls. Qualitative reviews of this literature implicate the orbitofrontal cortex, caudate nuclei, and thalamus. In this study, a meta-analysis was conducted to summarize the results of studies using positron emission tomography (PET) and single photon emission computed tomography (SPECT) to investigate brain activity in OCD. Results suggest that differences in radiotracer uptake between patients with OCD and healthy controls have been found consistently in the orbital gyrus and the head of the caudate nucleus. No other significant differences were found. The implications of these results for theories regarding the etiology of OCD are discussed.

Despite the recent rise in oral methylphenidate (MPH) abuse, few studies have characterized the time course of oral MPH brain effects in human subjects. Accordingly, this study assessed the hemodynamic effects of oral MPH effects in 11 healthy young adults (six women), by measuring brain transverse relaxation times (T2). T2 can be interpreted as a surrogate marker for, and inversely correlated with, steady-state cerebral blood volume (CBV). Data were acquired from the caudate nucleus, putamen, and thalamus, using a 1.5 T MRI scanner at baseline and serially for 2 h following oral MPH administration (0.5 mg/kg). Physiological and subjective measures and plasma MPH levels also were examined. MPH induced a selective T2 decrease (-1.65+/-0.53 ms) in the putamen (F(6,54)=2.68, P<0.03). Heartrate, blood pressure and plasma MPH levels increased significantly after drug administration, as well as subjective ratings of "feeling drug effect". T2 decreases may reflect MPH-induced increases in putaminal blood volume. These data suggest that T2 relaxometry can be used to study the time course of regional cerebral blood volume responses to MPH and perhaps to other stimulant drugs.

Developmental venous anomalies (DVAs) are common variants of cerebral venous drainage that are typically incidental findings on contrast-enhanced MR imaging studies. We present four cases of asymptomatic DVAs that demonstrate increased cerebral blood flow, cerebral blood volume, mean transit time, and time to peak on perfusion MR images. Our study indicates that alterations in perfusion MR imaging parameters can be seen with uncomplicated DVAs and do not necessarily imply a more ominous underlying etiologic factor, such as hypervascular tumor or stroke., (Copyright American Society of Neuroradiology)

The present study employs selective estrogen receptor (ER) agonists to determine whether 17beta-estradiol-induced neuroprotection in global ischemia is receptor mediated and, if so, which subtype of receptor (ERalpha or ERbeta) is predominantly responsible. Halothane-anesthetized female C57Bl/6J mice were ovariectomized, and osmotic minipumps containing ERbeta agonist diarylpropiolnitrile (DPN) (8 mg.kg(-1).day(-1), n = 12) or vehicle (50% DMSO in 0.9% saline) (n = 9) or ERalpha agonist propyl pyrazole triol (PPT) (2 mg.kg(-1).day(-1), n = 13) or vehicle (50% DMSO in 0.9% saline) (n = 10) were implanted subcutaneously. One week later transient global ischemia was induced by bilateral carotid artery occlusion under halothane anesthesia, and the mice were perfusion fixed 72 h later. ERbeta agonist DPN significantly reduced ischemic damage by 70% in the caudate nucleus and 55% in the CA1 region compared with vehicle controls (P < 0.05, Mann-Whitney U-statistic). In contrast, pretreatment with the ERalpha agonist PPT had no effect on the extent of neuronal damage compared with controls. The data indicate a significant estrogen receptor-mediated neuroprotection in a global cerebral ischemia model involving ERbeta.

Obsessive compulsive disorders (OCD) may be encountered after basal ganglia lesions of various aetiologies. These lesions are usually bilateral. We report here the case of a 24 years old man who developed a pure compulsive behavior after a unilateral left-sided caudate nucleus hemorrhage due to a cavernoma. The pathophysiology of this compulsive disorder probably reflects a frontal cortex deafferentation mechanism. Behavioral, psychological and medical (serotoninergic) treatments are usually proposed but the efficacy of such therapy remains to be investigated in secondary OCD.

Purpose: Ictal-interictal single-photon emission computed tomography (SPECT) subtraction was performed to find brain structures related to ictal dystonic posturing (DP) in patients with temporal lobe epilepsy (TLE)., Methods: Thirty-two patients with mesial TLE who had ictal and interictal SPECTs were included. They were divided into two groups; DP group with ictal dystonia during ictal SPECT (n = 15) and Non-DP group without ictal DP (n = 17). Ictal-interictal SPECT subtraction was performed, and then subtracted SPECT was coregistered with brain spoiled gradient recalled (SPGR) magnetic resonance imaging (MRI). The ictal hyperperfusion on subtracted SPECT was analyzed in basal ganglia, frontal cortex, thalamus, temporal lobe, and insular cortex., Results: The incidences of ictal hyperperfusion on brain regions in DP versus Non-DP groups were 80.0% (12 of 15 patients) versus none (0 of 17), p = 0.001, chi2, in caudate nucleus; 93.3% (14 of 15) versus 47.0% (eight of 17), p = 0.005, in putamen; and 80.0% (12 of 15) versus 41.2% (seven of 17), p = 0.026, in thalamus. No significant difference of ictal hyperperfusion was found in globus pallidus, temporal lobes, insular and frontal cortices between DP and Non-DP groups. DP patients showed an earlier age at seizure onset [8.6 years (DP) vs. 15.7 years (Non-DP) (p = 0.015)] and a longer duration of seizure history [19.0 years (DP) vs. 11.9 years (Non-DP) (p = 0.015)]., Conclusions: Caudate nucleus, putamen, and thalamus were significantly related to the ictal DP during TLE seizures. Our study showed first an active involvement of the caudate nucleus in the generation of ictal DP.

Research has increasingly implicated the striatum in the processing of reward-related information in both animals and humans. However, it is unclear whether human striatal activation is driven solely by the hedonic properties of rewards or whether such activation is reliant on other factors, such as anticipation of upcoming reward or performance of an action to earn a reward. We used event-related functional magnetic resonance imaging to investigate hemodynamic responses to monetary rewards and punishments in three experiments that made use of an oddball paradigm. We presented reward and punishment displays randomly in time, following an anticipatory cue, or following a button press response. Robust and differential activation of the caudate nucleus occurred only when a perception of contingency existed between the button press response and the outcome. This finding suggests that the caudate is involved in reinforcement of action potentially leading to reward, rather than in processing reward per se.

Regional cerebral blood flow (CBF) was studied with O(15)-water positron emission tomography and anatomic region-of-interest analysis on co-registered magnetic resonance in patients with idiopathic (n = 12) and secondary (n = 5) normal pressure hydrocephalus (NPH). Mean CBF was compared with values obtained from healthy volunteers (n = 12) and with clinical parameters. Mean CBF was significantly decreased in the cerebrum and cerebellum of patients with NPH. The regional analysis demonstrated that CBF was reduced in the basal ganglia and the thalamus but not in white matter regions. The results suggest that the role of the basal ganglia and thalamus in NPH may be more prominent than currently appreciated. The implications for theories regarding the pathogenesis of NPH are discussed.

A pertinent question in biological psychiatry is what differentiates responders and non-responders to pharmacological treatment. One possibility is that individual differences in the symptomatic spectrum as well as in the underlying biology of the disorder lead to the known 40% failure in pharmacological treatment. Our study aimed to maximize individual brain markers of obsessive-compulsive disorder (OCD) by applying single photon emission computed tomography (SPECT) during a provoked symptomatic state prior to and following treatment. Four brain SPECT scans were obtained from 26 OCD patients prior to and at 6 months of sertraline treatment. At each time point, two SPECT scans were performed in a counterbalanced order of two specific states; one a symptom-provoking condition and the other a relaxed condition. At 6 months of treatment, patients were divided into responders and non-responders according to a predetermined clinical criterion. Prospective responders showed significantly lower brain perfusion in the dorsal-caudal anterior cingulum and higher brain perfusion in the right caudate, when compared to non-responders, only during symptom provocation. When pre- and post-treatment scans during symptom provocation were compared, only responders showed significant change in brain response: increased perfusion in the left anterior temporal cortex and prefrontal cortex at 6 months' treatment. These findings suggest that obtaining functional brain imaging during specific symptom provocation emphasizes individual differences in brain reactivity. Thus can indicate prospective responders to symptom-related treatment in OCD and mark the relevant brain regions for effective response to treatment.

Background: Little is known about serotonin neurons in Parkinson disease (PD)., Objective: To study the serotonin system in PD with positron emission tomography, using the serotonin transporter radioligand [11C](+)McN5652., Design and Patients: We measured the density of the serotonin transporter and the density of [11C]WIN35,428-labeled dopamine transporters in the striatum of 13 adults with PD and 13 age- and sex-matched controls. To assess the effects of possible differences in blood flow or brain atrophy, we also measured regional cerebral blood flow and the size of the regions of interest for the caudate nucleus and putamen., Results: Patients with PD showed reductions in the specific distribution volumes of [11C](+)McN5652 in the caudate (P<.01) and putamen (P<.01), along with the expected reductions in striatal [11C]WIN35,428 binding (P<.01). There were no reductions in regional cerebral blood flow or the sizes of the regions of interest, mitigating against potential confounding effects of blood flow, brain atrophy, or partial volume effects. Reductions in serotonin transporter binding correlated with ratings of disease staging., Conclusions: These results suggest that the density of serotonin transporters, like that of dopamine transporters, is reduced in the striatum of patients with PD and that these changes are related to disease stage.

Objective: This study, part of a continuing effort to understand the pathophysiology of the brain in early-onset anorexia nervosa, attempts to validate findings from an earlier study of regional cerebral blood flow and to correlate any abnormalities in blood flow with eating disorder psychopathology., Method: Fifteen newly referred children and adolescents with a diagnosis of anorexia nervosa (AN) underwent regional cerebral blood flow (rCBF) examination using single-photon computerized tomography (SPECT) and the Eating Disorders Examination (EDE) for children., Results: Mean age was 14 years 11 months (SD = 1.35). Mean weight for height ratio was 82.79 % (SD = 10.66). SPECT findings showed that 11 (73%) had asymmetry (hypoperfusion) of blood flow in at least one area. Regions of the brain showing hypoperfusion included the temporal lobe (n = 9), parietal lobe (n = 5), frontal lobe (n = 3), thalamus (n = 3), and the caudate nuclei (n = 1). The median EDE subscale scores were high for all four subscales. Those patients with hypoperfusion had higher median EDE subscale scores than those without hypoperfusion, although the differences were not statistically significant., Conclusions: Most patients in our study had abnormal rCBF, predominantly affecting the temporal lobe, confirming our previous findings. There was no association with the EDE scores. The findings support earlier suggestions of an imbalance in neural pathways or circuits, possibly within the limbic system. This hypothesis is considered within the context of current knowledge and suggestions made with regard to how it might be tested., (Copyright 2003 by Wiley Periodicals, Inc.)

The identification of Nocardia transvalensis, an unusual and probably underrecognized cause of nocardial infection, is clinically significant because of this species' resistance to aminoglycosides, a standard antinocardial therapy. Diagnosis requires analytic methods available predominately in reference laboratories. We report a case of disseminated infection with N transvalensis with primary pulmonary involvement and subsequent development of brain abscesses, and review the literature to date. Familiarity with the epidemiology, pathologic findings, and clinical significance of this and other unusual Nocardia species may increase early identification and antibiotic susceptibility testing in cases of nocardial infection.

Background: Interruptions in SSRI treatment have been associated with adverse effects that can resemble depressive illness. We hypothesized that brain regions implicated in depression, with extensive serotonergic innervation, would exhibit changes in activity associated with emergence of symptoms following drug discontinuation., Methods: Subjects meeting DSM-IV criteria for remitted major depression on 20 mg/day of either fluoxetine or paroxetine were recruited into this 6-week study. During weeks 2 and 6, subjects underwent a 3-day period in which either active drug or placebo was substituted for their medication under double-blind conditions. Cerebral blood volume (CBV) maps were obtained via dynamic susceptibility magnetic resonance imaging at the end of each double-blind period., Results: In the paroxetine group, change in CBV in left medial superior frontal region and left caudate nucleus correlated significantly with change in Discontinuation Emergent Symptom Scale and Hamilton Depression Rating Scale (HDRS; R2 = 0.66, p =.0007; R2 = 0.51, p =.006; and R2 = 0.43, p =.015; R2 = 0.32, p =.043, respectively)., Conclusions: These data demonstrate that changes in regional CBV of left prefrontal cortex and left caudate nucleus correlate with the emergence of discontinuation symptoms and increased HDRS after interruption of paroxetine treatment.

Clinical-neuropsychological investigations were performed in 187 patients with arteriovenous malformations (AVM) of deep brain structures; 28 had AVM of the caudate nucleus, 35 of the thalamus, 45 of the cingulate gyrus, 43 of the hippocampus, and 36 of the corpus callosum. A total of 47 patients displayed neglect phenomena of different modalities, while unfixed neglect was demonstrated in 40 cases using special tests. The vast majority of patients showed neglect of left-sided space and the left side of the body, while only three patients showed right-sided neglect. These three patients had signs of left-handedness. In the development of neglect in all patients was associated with post-hemorrhagic or post-operative damage to the white matter (the projections of sensory bundles of the parietal and occipital lobes, the periventricular white matter) or the thalamus and corpus callosum. In hemispheric lesions, neglect developed on the background of the corresponding derangements (hemihypesthesia hemianopsia) and were of the same modality. In cases of damage to the corpus callosum, neglect could develop without accompanying sensory disturbances or the phenomenon could occur on different sides (in cases of simultaneous left hemisphere damage). This supports the independent nature of the neglect phenomenon.

The authors studied the differences between heat-shock/stress protein 70 (hsp70) gene expression and protein synthesis in the unilateral middle cerebral artery (MCA) microsurgical direct occlusion (Tamura's) model and the unilateral intraluminal occlusion model. In Tamura's model, expression of hsp70 mRNA and HSP70 protein and decreased protein synthesis were detected in the ischemic areas, including the ipsilateral cortex and caudate. These phenomena, however, were not observed in the areas outside the MCA territory, including the ipsilateral thalamus, hippocampus, and substantia nigra. These results were consistent among the experimental rats. In the intraluminal occlusion model, however, induction of both hsp70 mRNA and HSP70 protein and impairment of protein synthesis were noted in the areas outside the MCA territory, including the ipsilateral thalamus, hypothalamus, hippocampus, and substantia nigra, as well as in the MCA territory, including the ipsilateral cortex and caudate. These results were not consistent among the experimental rats. These different results might be due to widespread damage resulting from internal carotid artery (ICA) occlusion in the intraluminal occlusion model. Accordingly, the authors suggest that this model be called an ICA occlusion model, rather than a pure MCA occlusion model.

Objective: To investigate the response of the brains of women to the ingestion of a meal., Research Methods and Procedures: We used measures of regional cerebral blood flow (rCBF), a marker of neuronal activity, by positron emission tomography to describe the functional anatomy of satiation, i.e., the response to a liquid meal in the context of extreme hunger (36-hour fast) in 10 lean (BMI < or = 25 kg/m(2); 32 +/- 10 years old, 61 +/- 7 kg; mean +/- SD) and 12 obese (BMI > or = 35 kg/m(2); 30 +/- 7 years old, 110 +/- 14 kg) women., Results: In lean and obese women, satiation produced significant increases in rCBF in the vicinity of the prefrontal cortex (p < 0.005). Satiation also produced significant decreases in rCBF in several regions including the thalamus, insular cortex, parahippocampal gyrus, temporal cortex, and cerebellum (in lean and obese women), and hypothalamus, cingulate, nucleus accumbens, and amygdala (in obese women only; all p < 0.005). Compared with lean women, obese women had significantly greater increases in rCBF in the ventral prefrontal cortex and had significantly greater decreases in the paralimbic areas and in areas of the frontal and temporal cortex., Discussion: This study indicates that satiation elicits differential brain responses in obese and lean women. It also lends additional support to the hypothesis that the paralimbic areas participate in a central orexigenic network modulated by the prefrontal cortex through feedback loops.

Comparative studies have implicated the nucleus accumbens (NAcc) in the anticipation of incentives, but the relative responsiveness of this neural substrate during anticipation of rewards versus punishments remains unclear. Using event-related functional magnetic resonance imaging, we investigated whether the anticipation of increasing monetary rewards and punishments would increase NAcc blood oxygen level-dependent contrast (hereafter, "activation") in eight healthy volunteers. Whereas anticipation of increasing rewards elicited both increasing self-reported happiness and NAcc activation, anticipation of increasing punishment elicited neither. However, anticipation of both rewards and punishments activated a different striatal region (the medial caudate). At the highest reward level ($5.00), NAcc activation was correlated with individual differences in self-reported happiness elicited by the reward cues. These findings suggest that whereas other striatal areas may code for expected incentive magnitude, a region in the NAcc codes for expected positive incentive value.

Background: Formal thought disorder (FTD) is a core symptom of schizophrenia, but its pathophysiology is little understood. We examined the neural correlates of FTD using functional magnetic resonance imaging., Methods: Blood oxygenation level-dependent contrast was measured using functional magnetic resonance imaging while 6 patients with schizophrenia and 6 control subjects spoke about 7 Rorschach inkblots for 3 minutes each. In patients, varying degrees of thought-disordered speech were elicited during each "run." In a within-subject design, the severity of positive FTD was correlated with the level of blood oxygenation level-dependent contrast in the 2 runs that showed the highest variance of FTD in each patient., Results: The severity of positive FTD in patients was negatively correlated (P<.001) with signal changes in the left superior and middle temporal gyri. Positive correlations were evident in the cerebellar vermis, the right caudate body, and the precentral gyrus., Conclusions: The severity of positive FTD was inversely correlated with the level of activity in the Wernicke area, a region implicated in the production of coherent speech. Reduced activity in this area might contribute to the articulation of incoherent speech. Because of the small sample size, these findings should be considered preliminary.

Functional brain mapping based on changes in local cerebral blood flow (lCBF) or glucose utilization (lCMR(glc)) induced by functional activation is generally carried out in animals under anesthesia, usually alpha-chloralose because of its lesser effects on cardiovascular, respiratory, and reflex functions. Results of studies on the role of nitric oxide (NO) in the mechanism of functional activation of lCBF have differed in unanesthetized and anesthetized animals. NO synthase inhibition markedly attenuates or eliminates the lCBF responses in anesthetized animals but not in unanesthetized animals. The present study examines in conscious rats and rats anesthetized with alpha-chloralose the effects of vibrissal stimulation on lCMR(glc) and lCBF in the whisker-to-barrel cortex pathway and on the effects of NO synthase inhibition with N(G)-nitro-L-arginine methyl ester (L-NAME) on the magnitude of the responses. Anesthesia markedly reduced the lCBF and lCMR(glc) responses in the ventral posteromedial thalamic nucleus and barrel cortex but not in the spinal and principal trigeminal nuclei. L-NAME did not alter the lCBF responses in any of the structures of the pathway in the unanesthetized rats and also not in the trigeminal nuclei of the anesthetized rats. In the thalamus and sensory cortex of the anesthetized rats, where the lCBF responses to stimulation had already been drastically diminished by the anesthesia, L-NAME treatment resulted in loss of statistically significant activation of lCBF by vibrissal stimulation. These results indicate that NO does not mediate functional activation of lCBF under physiological conditions.

Background and Purpose: The purpose of the present study was to analyze the outcome and outcome predictors of caudate hemorrhage and role of external ventricular drainage in acute hydrocephalus., Methods: Clinical data from 36 consecutive patients with hypertensive caudate hemorrhage was used in the present study. Age, gender, volume of parenchymal hematoma, hematoma in the internal capsule, initial Glasgow Coma Scale (GCS), hydrocephalus, severity of intraventricular hemorrhage, and hemorrhagic dilatation of the fourth ventricle were analyzed for effect on outcome. Effect of external ventricle drainage for hydrocephalus was evaluated by comparing preoperative and postoperative GCS scores., Results: By univariate analyses, poor outcome was associated with a poor initial GCS score (P=0.016), hydrocephalus (P<0.001), intraventricular hemorrhage severity (P<0.01), and hemorrhagic dilatation of the fourth ventricle (P=0.02). By multivariate analysis, stepwise logistic regression revealed that hydrocephalus was the only independent prognostic factor for poor outcome (P<0.001). Postoperative 48-hour GCS score was better than the preoperative score by use of paired-sample t test (P<0.001)., Conclusions: Hydrocephalus is the most important predictor of poor outcome. External ventricular drainage response for hydrocephalus was good in the present study, whereas an early decision should be made regarding preoperative neurological condition.

Previous work has identified the prefrontal cortex (PFC) and striatum as participating in the planning and selection of movements. We compared the brain activation patterns during planning in Parkinson's disease patients and age-matched controls using H(2)(15)O-PET and the Tower of London (TOL) task. In this study, our mildly affected Parkinson's disease group performed as well as the control group but showed a different pattern of neuronal activation. In the two groups, overlapping areas of the PFC were activated but, whereas the right caudate nucleus was activated in the control group, this was not evident in the Parkinson's disease patients. This suggests that normal normal frontal lobe activation can occur in Parkinson's disease despite abnormal processing within the basal ganglia. Moreover, right hippocampus activity was suppressed in the controls and enhanced in the Parkinson's disease patients. This could represent a shift to the declarative memory system in Parkinson's disease during performance of the TOL task, possibly resulting from insufficient working memory capacity within the frontostriatal system.

This study characterizes the regional changes in vascularity, which accompanies chronic progressive hydrocephalus. Fifteen dogs underwent surgical induction of hydrocephalus and were used for histologic studies. Animals were divided into 4 groups: surgical control, short term (< or = 5 weeks), intermediate term (8 weeks), and long term (10 to 12 weeks). Vessel diameter, density, and luminal area were calculated by imaging quantification after manual vessel identification in the cortical gray, white matter, and caudate nucleus. Capillary vessel diameter decreased 23.5% to 30.2% (P < 0.01) in the caudate, but then returned to normal at 12 weeks. Capillary vessel density decreased 53.5% (P < 0.05) in the cortical gray, but then increased to 234.8% (P < 0.01) over surgical controls at 12 weeks. There was no initial decrease in capillary density in the caudate; however, the long-term group capillary density was significantly greater (172.8% to 210.5%, P < 0.01) than surgical controls. Overall, there was a short-term decrease in lumen area, with recovery in the longer term. Glial fibrillary acidic protein (GFAP) immunohistochemistry demonstrated the pattern of GFAP staining and reactive astrocytes differed in the caudate compared with the occipital cortex. This data suggest that an increase in capillary density and diameter may be an adaptive process allowing maintenance of adequate cerebral perfusion and metabolic support in the hypoxic environment of chronic hydrocephalus.

Background: Executive control of cognition, emotion, and behavior are disrupted in the manic state of bipolar disorder. Whereas frontal systems are implicated in such dysfunction, the localization of functional brain abnormalities in the manic state is not well understood., Methods: We utilized a high-sensitivity H(2)(15)0 positron emission tomography technique to investigate regions of increased brain activity in mania, compared to euthymia, in bipolar disorder., Results: The principal findings were manic state-related increased activity in left dorsal anterior cingulate, and left head of caudate., Conclusions: The findings suggest that the manic state of bipolar disorder may be associated with heightened activity in a frontal cortical-subcortical neural system that includes the anterior cingulate and caudate.

Research suggests that the basal ganglia complex is a major component of the neural circuitry that mediates reward-related processing. However, human studies have not yet characterized the response of the basal ganglia to an isolated reward, as has been done in animals. We developed an event-related functional magnetic resonance imaging paradigm to identify brain areas that are activated after presentation of a reward. Subjects guessed whether the value of a card was higher or lower than the number 5, with monetary rewards as an incentive for correct guesses. They received reward, punishment, or neutral feedback on different trials. Regions in the dorsal and ventral striatum were activated by the paradigm, showing differential responses to reward and punishment. Activation was sustained following a reward feedback, but decreased below baseline following a punishment feedback.

This study was designed to compare the role of the newly described endogenous opioid nociceptin/orphanin FQ (NOC/oFQ) in the reductions of cerebral blood flow (CBF) and pial artery diameter observed following fluid percussion brain injury (FPI) in chloralose anesthetized newborn and juvenile pigs as a function of time postinsult. FPI elevated CSF NOC/oFQ concentration from 70 +/- 3 to 444 +/- 51 within 1 h and to 1,931 +/- 112 pg/mL (n = 7) within 8 h, whereas concentrations returned to control value within 168 h in the newborn. In contrast, FPI elevated CSF NOC/oFQ from 77 +/- 4 to 202 +/- 16 pg/mL (n = 7) within 1 h, while values returned to control value within 8 h in the juvenile. Topical NOC/oFQ (10(-8), 10(-6) M) induced vasodilation was reversed to vasoconstriction by FPI in the newborn while such responses were only attenuated in the juvenile at 1 h post insult (control, 9 +/- 1 and 16 +/- 1%; FPI newborn, -8 +/- 1 and -14 +/- 1%; FPI juvenile, 2 +/- 1 and 5 +/- 1%, n = 7). Such altered dilation returned to control value within 168 h in newborns and 8 h in juveniles. Blood flow in the cerebrum was reduced from 57 +/- 4 to 23 +/- 3 mL x min(-1) x 100 g(-1) (n = 7) within 1 h and returned to control value with 168 h post FPI in newborns. In animals pretreated with [F/G] NOC/oFQ (1-13) NH2 (1 mg/kg, i.v.), a NOC/oFQ antagonist, however, CBF only fell to 39 +/- 4 mL x min(-1) x 100 g(-1) (n = 7) at 1 h post insult in newborns. In contrast, CBF was only reduced from 57 +/- 6 to 32 +/- 2 in untreated and to 39 +/- 3 mL/min(-1) x 100 g(-1) (n = 7) in treated juveniles within 1 h post FPI. Similar observations for reductions in pial artery diameter were made in untreated and treated newborns and juveniles. These data suggest that an elevated CSF NOC/oFQ concentration and altered vascular responsiveness to this opioid contribute to reductions in CBF and pial artery diameter observed following FPI. Because such NOC/oFQ changes were greater in newborns versus juveniles, these data further suggest that NOC/oFQ contributes to age-related cerebral hemodynamic differences in the effects of FPI.

Unlabelled: Previous research using functional transcranial Doppler sonography showed that blood flow velocity in the anterior cerebral artery is significantly less in patients with Huntington's disease (HD) than in healthy volunteers while they are completing mazes. The current research used SPECT to study regional cerebral blood flow (rCBF) in patients with HD during rest and maze testing., Methods: Seven patients with HD and 9 healthy volunteers were injected twice with 0.96-1.15 GBq 99mTc-labeled hexamethylpropylene amine oxime. During the 10 min after injection, subjects either solved mazes or rested with their eyes open while looking at a modified maze. After SPECT, count density was obtained from 11 brain regions and corrected for decay and injected dose. Two types of data generated from this experiment, including absolute regional counts per pixel in the regions of interest and count density computed as a percentage of activity in the lateral cerebellum, were compared between groups., Results: During rest, the absolute regional count density was greater in the HD brains than in the healthy brains (P < 0.001). Count density was typically between 8% and 13% higher in the HD group than in the healthy group. The single exception was the caudate density, for which the 2 groups had similar values. No significant differences in absolute regional count density were observed between groups during maze testing. When rCBF was calculated as a percentage of cerebellar rCBF, analysis of covariance found decreases in HD caudate density (P < 0.001) and orbital frontal cortex density (P < 0.005) during maze testing. Changes in rCBF in the caudate nucleus predicted gene status (P = 0.0007) and correlated with time to complete the mazes (P < 0.05)., Conclusion: Patients with HD showed an increase in resting rCBF for all brain regions measured except the caudate nucleus. When rCBF was calculated as a percentage of cerebellar blood flow, rCBF in the striatum and orbital cortex in patients with HD was less during maze testing than during rest. Although the cause of these rCBF changes in HD patients is unclear, nitric oxide synthase, a regulator of vasomotor activity, may be involved.

We used PET to study differences in cerebral blood flow (CBF) in smooth pursuit, predictive saccades and fixation. Eye movements were monitored in the scanner. Compared with fixation, pursuit and predictive saccades activated a network of highly similar areas, including frontal eye fields, supplementary eye fields, V5 and medial cuneus. Our findings are consistent with non-human primate studies that suggest that pursuit and saccades are controlled by similar and adjacent neural areas. Pursuit was associated with greater activation of caudate than saccades, suggesting a role for basal ganglia in pursuit that is consistent with studies of neurological populations. Saccades were associated with greater activation of cerebellum and frontal eye fields. A frontal-cerebellar loop may be important in coordinating the preparation and timing of saccades in predictive tracking.

Background: We investigated the cerebral blood flow in mild to moderately hypertensive patients with chronic cerebral infarction before and after the administration of bunazosin hydrochloride sustained-release formulation, a selective sympathetic alpha1 receptor blocker., Methods: Eleven mild to moderately hypertensive patients (mean age 65.6 years) with chronic cerebral infarction were studied., Interventions: The patients were on enalapril maleate, an angiotensin converting enzyme inhibitor, for one week and then enalapril maleate was switched to bunazosin hydrochloride sustained-release formulation., Measures: The cerebral blood flow study was performed before and 8 weeks after starting the administration of bunazosin hydrochloride sustained-release formulation. Cerebral blood flow was measured using the stable xenon CT method. The picture analysis was performed using AZ-7000. The regional cerebral blood flow was measured by placing the region of interest on the CT images. The regional cerebral blood flows were measured before and 20 minutes after intravenous injection of 17 mg/kg acetazolamide., Results: The blood flows in the parietal cortex and caudate nucleus 8 weeks after starting the administration of bunazosin hydrochloride sustained-release formulation were significantly greater than those before. The cerebrovascular acetazolamide reactivity in the occipital cortex and caudate nucleus was significantly lower after switching to bunazosin hydrochloride sustained-release formulation than before., Conclusions: Considering the reports that angiotensin converting enzyme inhibitors show little influence on cerebral blood flow, the present study suggests that bunazosin hydrochloride sustained-release formulation may show a good influence on cerebral blood flow in mild to moderately hypertensive patients with chronic cerebral infarction.

Purpose: The purpose of this work was to describe the deep vascular anatomy of the human brain using high resolution MR gradient echo imaging at 8 T., Method: Gradient echo images were acquired from the human head using a transverse electromagnetic resonator operating in quadrature and tuned to 340 MHz. Typical acquisition parameters were as follows: matrix = 1,024 x 1,024, flip angle = 45 degrees, TR = 750 ms, TE = 17 ms, FOV = 20 cm, slice thickness = 2 mm. This resulted in an in-plane resolution of approximately 200 microm. Images were analyzed, and vascular structures were identified on the basis of location and course., Results: High resolution ultra high field magnetic resonance imaging (UHFMRI) enabled the visualization of many small vessels deep within the brain. These vessels were typically detected as signal voids, and the majority represented veins. The prevalence of the venous vasculature was attributed largely to the magnetic susceptibility of deoxyhemoglobin. It was possible to identify venous structures expected to measure below 100 microm in size. Perforating venous drainage within the deep gray structures was identified along with their parent vessels. The course of arterial perforators was more difficult to follow and not as readily identified as their venous counterparts., Conclusion: The application of high resolution gradient echo methods in UHFMRI provides a unique detailed view of particularly the deep venous vasculature of the human brain.

Caudate strokes comprise only a small proportion of all subtypes of strokes. Bilateral caudate infarcts are even rarer and only a few cases have been reported in the literature. We report an 86-year-old woman with bilateral caudate infarcts. She had no past medical history of note. She presented with headache for several days and drowsiness on day of admission. Clinical examination revealed abulia, inability to comprehend or verbalize (acute mutism), right-sided neglect and right-sided hemiparesis. Computed tomographic (CT) scan brain revealed decreased attenuation in both heads of both caudate nuclei with extension across the anterior limb of both internal capsules to involve the lentiform nuclei. Echocardiography showed aortic valve sclerosis, mild mitral and aortic regurgitation and normal left ventricular function. Carotid ultrasound revealed mild stenosis of proximal right internal carotid and left distal common carotid and adjacent proximal internal carotid arteries. She showed initial improvement in the first week, but subsequently had a progressive downward course despite rehabilitation and died 44 days after her stroke. A patient with bilateral caudate infarcts is likely to have poor prognosis for rehabilitation and survival.