Older adults often demonstrate higher levels of false recognition than do younger adults. However, in experiments using novel shapes without preexisting semantic representations, this age-related elevation in false recognition was found to be greatly attenuated. Two experiments tested a semantic categorization account of these findings, examining whether older adults show especially heightened false recognition if the stimuli have preexisting semantic representations, such that semantic category information attenuates or truncates the encoding or retrieval of item-specific perceptual information. In Experiment 1, ambiguous shapes were presented with or without disambiguating semantic labels. Older adults showed higher false recognition when labels were present but not when labels were never presented. In Experiment 2, older adults showed higher false recognition for concrete but not abstract objects. The semantic categorization account was supported.

Background and Purpose There are few population-based data regarding gender differences in signs and symptoms of acute ischemic stroke. Previously reported data have been inconsistent and conflicting. This study addresses these gender differences in a population-based study. Methods All patients with first ischemic stroke occurring in Rochester, MN residents during 1985-1989 were identified. Signs and symptoms were collected via review of the comprehensive medical records. Differences were identified by Pearson’s Chi-square test. Results Symptoms at ischemic stroke presentation differed between men and women as follows: Women more commonly presented with generalized weakness (p=0.005) and mental status change (p=0.0001). Men more commonly presented with paresthesia (p=0.003), ataxia (p=0.006), and double vision (p =0.005). Signs at ischemic presentation of stroke differed between men and women as follows: Men more commonly presented with nystagmus (p=0.002) on exam. Significant trends were that women more commonly presented with fatigue (p=0.02), disorientation (p=0.04), and fever (p=0.02), and men more commonly presented with sensory abnormalities (p=0.02). Conclusions There are differences by gender in signs and symptoms at presentation of ischemic stroke. In addition to selected focal symptoms, women more commonly present with diffuse symptoms of generalized weakness, fatigue, disorientation, and mental status change.

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Leukemia may initially present as a peripheral neuropathy, leading to a delay in diagnosis. Leukemic infiltration of peripheral nerves, or neuroleukemiosis (NL), is exceedingly rare, with no established diagnostic or therapeutic guidelines. Five cases are presented. All patients were men with a median age of 68 years (range 46-72). Three patients had acute myeloid leukemia (AML) and two had chronic lymphocytic leukemia (CLL). In two patients, leukemia presented with peripheral nerve involvement and both were found to have positive cerebrospinal fluid (CSF) cytology, making the diagnosis AML, despite negative bone marrow and peripheral smear. All patients had painful, progressive, motor and sensory deficits. Clinical patterns were mononeuropathy (n =1), multiple mononeuropathies (n =1) and plexopathy (n =3). Magnetic resonance imaging (MRI) detected mass lesions in 4/5 cases, with avid fluorodeoxyglucose (FDG) uptake on positron emission tomography (PET) useful in all of these for following clinical disease progression. Three cases of nerve biopsy were performed, two of which were diagnostic of leukemic infiltration. Radiation treatment rapidly relieved pain in patients with mass lesions, in combination with chemotherapy. Four patients had disease relapse, four systemic and one also in peripheral nerves. These cases are discussed in the context of the broader literature.

A wide range of devices is used to obtain intracranial electrocorticography recordings in patients with medically refractory epilepsy, including subdural strip and grid electrodes and depth electrodes. Penetrating depth electrodes are required to access some brain regions, and 1 target site that presents a particular technical challenge is the first transverse temporal gyrus, or Heschl gyrus (HG). The HG is located within the supratemporal plane and has an oblique orientation relative to the sagittal and coronal planes. Large and small branches of the middle cerebral artery abut the pial surface of the HG and must be avoided when planning the electrode trajectory. Auditory cortex is located within the HG, and there are functional connections between this dorsal temporal lobe region and medial sites commonly implicated in the pathophysiology of temporal lobe epilepsy. At some surgical centers, depth electrodes are routinely placed within the supratemporal plane, and the HG, in patients who require intracranial electrocorticography monitoring for presumed temporal lobe epilepsy. Information from these recordings is reported to facilitate the identification of seizure patterns in patients with or without auditory auras. To date, only one implantation method has been reported to be safe and effective for placing HG electrodes in a large series of patients undergoing epilepsy surgery. This well-established approach involves inserting the electrodes from a lateral trajectory while using stereoscopic stereotactic angiography to avoid vascular injury. In this report, the authors describe an alternative method for implantation. They use frameless stereotaxy and an oblique insertion trajectory that does not require angiography and allows for the simultaneous placement of subdural grid arrays. Results in 19 patients demonstrate the safety and efficacy of the method.