Psychiatric neurosurgery teams in the United States and Europe have studied deep brain stimulation (DBS) of the ventral anterior limb of the internal capsule and adjacent ventral striatum (VC/VS) for ...severe and highly treatment-resistant obsessive-compulsive disorder. Four groups have collaborated most closely, in small-scale studies, over the past 8 years. First to begin was Leuven/Antwerp, followed by Butler Hospital/Brown Medical School, the Cleveland Clinic and most recently the University of Florida. These centers used comparable patient selection criteria and surgical targeting. Targeting, but not selection, evolved during this period. Here, we present combined long-term results of those studies, which reveal clinically significant symptom reductions and functional improvement in about two-thirds of patients. DBS was well tolerated overall and adverse effects were overwhelmingly transient. Results generally improved for patients implanted more recently, suggesting a 'learning curve' both within and across centers. This is well known from the development of DBS for movement disorders. The main factor accounting for these gains appears to be the refinement of the implantation site. Initially, an anterior-posterior location based on anterior capsulotomy lesions was used. In an attempt to improve results, more posterior sites were investigated resulting in the current target, at the junction of the anterior capsule, anterior commissure and posterior ventral striatum. Clinical results suggest that neural networks relevant to therapeutic improvement might be modulated more effectively at a more posterior target. Taken together, these data show that the procedure can be successfully implemented by dedicated interdisciplinary teams, and support its therapeutic promise.
Although previous functional brain imaging studies have found that the insula responds selectively to facial expressions of disgust, it remains unclear whether the insula responds selectively to ...disgust-inducing pictures. In this fMRI study, healthy volunteers viewed pictures of contamination, human mutilation, attacks and neutral scenes during scanning, and then rated pictures for the 'basic' emotions. The anterior insula responded to contamination and mutilation but not attacks, while the ventral visual areas responded to attacks and mutilations more strongly than contamination. The above activations were predicted by disgust and arousal ratings respectively. Additionally, mutilations uniquely activated the right superior parietal cortex. These results support selective disgust processing at the insula, and suggest distinct neural responses to contamination and mutilation.
The neurobiology relating to the insatiable appetite observed in Prader-Willi syndrome (PWS) has not been fully characterised. Two functional magnetic resonance imaging (fMRI) scans were performed on ...each of three adults with PWS. The scans were carried out pre- and post-treatment with the antiepileptic topiramate, which had little effect on body weight and appetite in these subjects. Subjects fasted overnight and drank a 75 g dextrose solution prior to fMRI scans for measurement of brain activation levels during/after glucose ingestion. Following glucose administration, there was a significant delay in activation at the hypothalamus and other brain regions associated with satiety compared with previous data on obese volunteers. These regions include the insula, ventromedial prefrontal cortex, and nucleus accumbens. Individuals with PWS showed a mean latency of 24 min while in a previous study obese volunteers had shown a latency of 15 min and lean volunteers a latency of 10 min in the hypothalamus. Our results provide evidence towards a satiety dysfunction in the central nervous system of PWS patients.
Background: Mood, cognitive, and behavioural changes have been reported with deep brain stimulation (DBS) in the thalamus, globus pallidus interna, and anterior limb of the internal capsule/nucleus ...accumbens region. Objective: To investigate panic and fear resulting from DBS. Methods: Intraoperative DBS in the region of the right and then left anterior limb of the internal capsule and nucleus accumbens region was undertaken to treat a 52 year old man with treatment refractory obsessive-compulsive disorder (OCD). Mood, anxiety, OCD, alertness, heart rate, and subjective feelings were recorded during intraoperative test stimulation and at follow up programming sessions. Results: DBS at the distal (0) contact (cathode 0−, anode 2+, pulse width 210 ms, rate 135 Hz, at 6 volts) elicited a panic attack (only seen at the (0) contact). The patient felt flushed, hot, fearful, and described himself as having a “panic attack.” His heart rate increased from 53 to 111. The effect (present with either device) was witnessed immediately after turning the device on, and abruptly ceased in the off condition Conclusions: DBS of the anterior limb of the internal capsule and nucleus accumbens region caused severe “panic.” This response may result from activation of limbic and autonomic networks.
Background: Recently, anterior limb of the internal capsule and nucleus accumbens deep brain stimulation (DBS) has been used in the treatment of medication-refractory obsessive–compulsive disorder ...(OCD). This region has been previously explored with lesion therapy, but with the advent of DBS there exists the possibility of monitoring the acute and chronic effects of electrical stimulation. The stimulation-induced benefits and side effects can be reversibly and blindly applied to a variety of locations in this region. Objective: To explore the acute effects of DBS in the anterior limb of the internal capsule and nucleus accumbens region. Methods: Ten total DBS leads in five patients with chronic and severe treatment-refractory OCD were tested. Patients were examined 30 days after DBS placement and received either “sham” testing or actual testing of the acute effects of DBS (the alternative condition tested 30 days later). Results: Pooled responses were reviewed for comparability of distribution using standard descriptive methods, and relationships between the variables of interest were sought using χ2 analysis. A total of 845 stimulation trials across the five patients were recorded and pooled. Of these 16% were elicited from sham stimulation and 17% from placebo (0 V stimulation). A comparison of active to sham trials showed that sham stimulation was not associated with significant side effects or responses from patients. Non-mood-related responses were found to be significantly associated with the ventral lead contacts (0 and 1) (p = 0.001). Responses such as taste, smell and smile were strongly associated with the most ventral lead positions. Similarly, physiological responses—for example, autonomic changes, increased breathing rate, sweating, nausea, cold sensation, heat sensation, fear, panic and panic episodes—were significantly associated with ventral stimulation (p = 0.001). Fear and panic responses appeared clustered around the most ventral electrode (0). Acute stimulation resulted in either improved or worsened mood responses in both the dorsal and ventral regions of the anterior limb of the internal capsule. Conclusion: The acute effects of DBS in the region of the anterior limb of the internal capsule and nucleus accumbens, particularly when obtained in a blinded fashion, provide a unique opportunity to localise brain regions and explore circuitry.
Background: Problematic internet use has been described in the psychological literature as ‘internet addiction’ and ‘pathological internet use’. However, there are no studies using face-to-face ...standardized psychiatric evaluations to identify behavioral characteristics, psychiatric comorbidity or family psychiatric history of individuals with this behavior.
Methods: Twenty individuals with problematic internet use were evaluated. Problematic internet use was defined as (1) uncontrollable, (2) markedly distressing, time-consuming or resulting in social, occupational or financial difficulties and (3) not solely present during hypomanic or manic symptoms. Evaluations included a semistructured interview about subjects’ internet use, the Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders-IV (SCID-IV), family psychiatric history and the Yale–Brown Obsessive–Compulsive Scale (Y-BOCS) modified for internet use.
Results: All (100%) subjects’ problematic internet use met DSM-IV criteria for an impulse control disorder (ICD) not otherwise specified (NOS). All 20 subjects had at least one lifetime DSM-IV Axis I diagnosis in addition to their problematic internet use (mean±SD=5.1±3.5 diagnoses); 14 (70.0%) had a lifetime diagnosis of bipolar disorder (with 12 having bipolar I disorder).
Limitations: Methodological limitations of this study included its small sample size, evaluation of psychiatric diagnoses by unblinded investigators, and lack of a control group.
Conclusions: Problematic internet use may be associated with subjective distress, functional impairment and Axis I psychiatric disorders.
Reduced appetite and weight loss were found in clinical trials of topiramate for epilepsy. Binge-eating disorder is characterized by recurrent episodes of binge eating that are not associated with ...regular use of inappropriate compensatory behaviors. Overweight and obesity may be common complications. To explore the effectiveness and tolerability of topiramate in binge-eating disorder, we describe the response of 13 consecutive outpatients with binge-eating disorder to naturalistic, open-label treatment with topiramate.
The response of 13 female outpatients with binge-eating disorder by DSM-IV criteria to naturalistic, open-label treatment with topiramate (100-1400 mg/day) was reviewed. Response of binge-eating disorder symptoms was clinically assessed as none, mild, moderate, marked, or remission. Weight and side effects were also evaluated.
All 13 patients had comorbid Axis I psychiatric disorders along with binge-eating disorder and were receiving psychotropic medications at the time of topiramate administration. After beginning topiramate treatment, 9 patients displayed a moderate or better response of binge-eating disorder symptoms that was maintained for periods ranging from 3 to 30 months (mean +/- SD = 18.7+/-8.0 months). Two other patients displayed moderate or marked responses that subsequently diminished. The remaining 2 patients had a mild or no response. The mean +/- SD weight of the 13 patients decreased from 99.3+/-26.4 kg to 87.5+/-20.4 kg (z = -2.4, df = 1, p = .02), but only 7 patients lost > or = 5 kg of weight. The mean topiramate treatment dose was 492.3+/-467.8 mg/day for all 13 patients. The mean topiramate dose was higher in patients who lost > or = 5 kg than in patients who lost < 5 kg. Also, topiramate dose correlated significantly with weight loss (p < .01). In general, topiramate was well tolerated, with neurologic side effects the most common. Of 3 patients who discontinued topiramate because of side effects, 2 resumed the drug at a later date without significant recurrence of these effects.
Topiramate may be an effective treatment for binge-eating disorder. Controlled studies of topiramate in binge-eating disorder appear warranted.
Deserts are characterized by unpredictable precipitation and extreme temperatures. Their fauna and flora are sensitive to anthropogenic environmental changes, and often recover slowly from ...environmental disasters. The effects of oil spills on the biota of desert regions, however, have scarcely been studied. We predicted that terrestrial invertebrates suffer long-term negative effects from an oil spill, due to their close association with the substrate. Thus, we investigated the effects of two oil spills that occurred in 1975 and 2014 in the hyper-arid 'Arava desert (Israel), on a spider that constructs silk-lined nests in burrows in compact, sandy soil in this extreme desert habitat. The spider,
sp. nov. (Filistatidae), is described herein. We assessed spider burrow abundance in plots located in oil-contaminated and nearby uncontaminated clean soil (control) areas over five consecutive years and measured habitat characteristics in these plots. In the laboratory, we determined the preference of individuals for clean vs. oil-contaminated soil as a resting substrate. Finally, as this species was previously undescribed, we added a new species description. The abundance of
was significantly lower in oil-contaminated plots, and this was the case in the 40-year-old oil spill (1975) as well as in the recent one (2014). In laboratory tests, spiders showed a significant preference for the clean soil substrate over the oil-contaminated substrate. In the field, soil crust hardness and vegetation density did not differ significantly between oil-contaminated and control plots, but these measures were highly variable. The burrows were significantly clustered, suggesting that the young disperse only short distances. In the laboratory adult spiders did not dig burrows, perhaps indicating that adults remain permanently in their natal burrows and that in the field they may use vacant burrows. We conclude that
populations were affected negatively by the oil spills and these effects were long-lasting. We propose that by monitoring their spatial distribution, burrow-dwelling spiders such as
can be used as effective bioindicators of soil pollution in desert habitats.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
In a case study, a 42-year-old married man with recurring depression spent several hours a day searching for particular pornographic images on the Internet. The patient's "pathological sexuality" is ...far from uncommon is more common in men than in women, and may cause a range of different behaviors.
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