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Recent evidence supports a role for genetics in autism, but other findings are difficult to reconcile with a purely genetic cause. Pathological changes in the cerebellum in autism are thought to correspond to an event before 30-32 weeks gestation. Our purpose was to determine whether there is an increased incidence of stressors in autism before this time period. Surveys regarding incidence and timing of prenatal stressors were distributed to specialized schools and clinics for autism and Down syndrome, and to mothers of children without neurodevelopmental diagnoses in walk-in clinics. Incidence of stressors during each 4-week block of pregnancy was recorded. Incidence of stressors in the blocks prior to and including the predicted time period (21-32 weeks gestation) in each group of surveys was compared to the other prenatal blocks. A higher incidence of prenatal stressors was found in autism at 21-32 weeks gestation, with a peak at 25-28 weeks. This does support the possibility of prenatal stressors as a potential contributor to autism, with the timing of stressors consistent with the embryological age suggested by neuroanatomical findings seen in the cerebellum in autism. Future prospective studies would be needed to confirm this finding.

OBJECTIVE Several deficits have been proposed to account for cognitive impairment in autism including an inability to comprehend the perspectives of others (“theory of mind”), an inability to process emotional information, and difficulty drawing together diverse information in context (“central coherence”). Because context (central coherence) and emotion can influence memory, a study was designed to show if autism spectrum disorder was associated with impaired utilisation of context and emotion in recall; and if impairments in theory of mind processing would influence recall in autism spectrum disorder. METHODS Ten high functioning subjects with autism spectrum disorder and 13 age and IQ matched controls were tested using recall tests. In the first coherence memory test, subjects listened to a series of word lists that were in varying degrees of syntactic and semantic (coherent) order and were asked to recall the words. In the second coherence memory test, subjects listened to stories consisting of sentences that were, or were not, in logical (coherent) order. In the emotional memory test, the subjects listened to sentences that were highly emotional or non-emotional. In the theory of mind test, the subjects listened to stories requiring varying levels of understanding of the perspectives of others. RESULTS There were no significant differences between groups in recall of coherent versus incoherent word lists, nor was there a significant difference between groups in recall of coherent versus incoherent stories. However, the control subjects recalled more of the emotional than non-emotional sentences, whereas the autism spectrum disorder group did not show such a difference. No significant difference existed in recall of stories requiring varying levels of understanding of the perspectives of others among subjects with autism spectrum disorder, and subjects with autism spectrum disorder did not differ from control subjects in the influence of theory of mind content on story recall. CONCLUSION The study shows that memory in high functioning adults with autism spectrum disorder is facilitated by emotional content to a lesser degree than it is facilitated by coherence. Therefore, impairments in emotional processing cannot be considered as simply an effect of the “weak central coherence” theory in autism spectrum disorder. Whereas the reasons for this emotional deficit are unknown, evidence of abnormalities of the limbic structures in autism spectrum disorder may provide an anatomical explanation.

Ingestion of fish or grain contaminated with methylmercury resulted in epidemics of severe neurotoxicity and death in Japan in the 1950s and 1960s1 and in Iraq in 1972.2 The World Health Organization and other organizations have warned of the dangers of methylmercury compounds to the environment and to scientific researchers.1,3–6 Dimethylmercury may be even more dangerous than methylmercury compounds. The physical properties of dimethylmercury permit transdermal absorption, and the volatility of this liquid permits toxic exposure through inhalation. Since dimethylmercury is lethal at a dose of approximately 400 mg of mercury (equivalent to a few drops, or about . . .

The serotonergic system is implicated in disordered emotional behavior. Autism is characterized by impaired processing of emotional information. The serotonergic (5-HT) system is also critically involved in brain development, and abnormal brain synthesis of serotonin is observed in autism. Furthermore, whole blood and platelet serotonin have been reported to be elevated in autism. The authors examined the CNS serotonin system in autism in vivo. 5-HT2 receptors were visualized by PET imaging of [18F]setoperone-binding in this pilot study of 6 high-functioning autistic adults and 10 matched-control participants. Autism subjects had less thalamic [18F]setoperone binding than controls, when covaried for age, but no difference reached significance in other areas. A negative relationship between thalamic binding and history of language impairment was also observed. Further studies will be needed to gain a clearer picture of the role of the 5-HT system in autism.

The occurrence of the rare but potentially fatal neuroleptic malignant syndrome must be considered by the surgeon treating a patient who develops hyperthermia, mental abnormalities, autonomic instability, and muscle rigidity after exposure to phenothiazines or other neuroleptic drugs. The dopamine agonist bromocriptine appears to be the treatment of choice in adults and seemed to be effective and well tolerated in our patient. Although the syndrome cannot be prevented, recognition is crucial, since effective general and specific therapy is available. Differentiating neuroleptic malignant syndrome from malignant hyperthermia allows early appropriate treatment with bromocriptine.

Introduction: The long-term outcome of pediatric patients undergoing corpus callosotomy (CC) for palliative control of medically intractable seizures is presented. Methods: During a 27-year period, 43 patients, 20 years of age or younger, underwent CC for seizure palliation and had a minimum of 1 year follow-up. Seizure reduction and stability of that outcome for individual seizure types and for most disabling seizure were reviewed. Results: Overall, 63% of the seizures documented showed a good response. For the most disabling seizure, 56% of the patients had good outcomes. Changes in outcome status occurred within the first 6 months, and outcome was largely maintained after that point. Conclusion: Callosotomy achieves the goal of seizure palliation in more than half of the patients, with stable, good outcomes being maintained in the majority of patients.

• The results of corpus callosotomy in 18 patients 16 years old and younger are presented. Eighty-three percent of our patients have had a significant improvement from the surgery (a decrease in seizure frequency of greater than 80% or no longer having generalized atonic, tonic, or tonic-clonic seizures). The procedure seems to be well tolerated in young patients, and we have not noted a postoperative deterioration in behavior, memory, or language function in our patients. One of our patients died in status epilepticus 3 months after surgery. Nevertheless, we have not encountered any serious morbidity in our other patients. Corpus callosotomy can be considered for children with intractable seizures, especially when generalized atonic, tonic, or tonic-clonic (whether primary or secondary) seizures are the major seizure type.

A 51-year-old diabetic woman developed bilateral rhinoorbitocerebral phycomycosis. Successful treatment was accomplished by correction of the ketoacidosis, surgical debridement, and amphotericin B therapy. Rhinoorbitocerebral phycomycosis is a fulminant and frequently fatal disease most often seen in debilitated hosts. This survival suggests that aggressive therapy is indicated in patients with extensive fungal involvement.