Increased intrusions during verbal recall in traumatic and nontraumatic lesions of the temporal lobe.

The mesial temporal and lateral frontal lobes were the most common sites of parenchymal abnormality on magnetic resonance imaging (MRI) scans for 12 patients with chronic traumatic brain injury (TBI). Ventricular widening was also common, and 3 patients showed increased size of the upper third ventricle. Of 10 right-handed TBI patients with no evidence of learning disability, 6 showed dominant temporal lesions and 3 showed an increase in the size of the upper third ventricle. Only patients with dominant temporal lesions (4 of 6) exceeded the normal confidence interval (based on 20 non-TBI controls) for intrusion errors on delay trials of the California Verbal Learning Test (CVLT), though other patients also demonstrated impaired recall. The pattern of increased intrusions during CVLT delay trials was confirmed in non-TBI patients who had undergone dominant temporal surgery or had dominant or bilateral temporal lesions, even when frontal changes could be ruled out. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Story and list recall tests as measures of verbal memory in a head-injured sample.

Memory components of story and list recall were derived for 48 head-injured patients (mean age 33.5 yrs) using regression techniques. Ss completed such measures as the Wechsler Memory Scale. General and verbal memory components, respectively, contributed the most variance to both story and list recall under both immediate and delayed conditions. Although they share substantial variance, list and story recall were not identical. Willingness to repeat oneself contributed to all types of recall, except delayed story recall. It was hypothesized that long-term storage contributed to immediate list recall ability, active semantic organization contributed to delayed list recall ability, and attentional fluctuations contributed to delayed story recall ability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Long-term reliability of silicon bipolar transistors subjected to low constraints

We present in this study the effect of electrical ageing on silicon (Si) NPN bipolar transistors. This study is based on a sample of half-hundred components, which have been fabricated in the early 1980s, which represents an exceptional experience feedback. By means of static and low frequency noise measurements, which are used as diagnostic tools for reliability assessment, we have noticed a good accordance with a physical model based on an oxide charge modulation. We have also used emission microscopy and electron beam-induced current analysis in order to visualize and to localize the defects in the structure. These have been located in the spacer oxide at the periphery of the base-emitter junction.     

Investigation of validity of WAIS—R short forms for patients suspected to have brain impairment.

Examined the validity of 2- and 4-subtest short forms of the WAIS—R proposed by A. B. Silverstein (see record 1982-24731-001) in 60 male Ss (mean age 50.3 yrs) referred for neuropsychological examination. Results yield estimates that were highly correlated with, but significantly greater than, the Full Scale IQ. Since short-form estimates frequently differed from the actual Full Scale IQ in terms of the manual intelligence classification, it is suggested that they provide positively biased estimates of general intelligence for some clinical populations. (3 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Use of the Luria-Nebraska Neuropsychological Battery in aphasia: A conceptual critique.

States that the Luria-Nebraska battery fails to distinguish between disturbances of language and other deficits, and fails to differentiate some types of language problems. Other difficulties, which apply to nonaphasic as well as aphasic populations, complicate the task of interpreting test data when an aphasic disturbance is present. (40 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Visual selective attention in parkinson's disease: Dissociation of exogenous and endogenous inhibition.

Impairment in the inhibitory mechanism of visual selective attention in patients with Parkinson's disease (PD) is controversial. The present study sought to understand disparate findings in a manner analogous to the relative preservation of exogenously evoked movement and impairment of endogenously evoked movement. The authors examined inhibition of return (i.e., exogenously evoked inhibition; IOR) and negative priming (i.e., endogenously evoked inhibition; NP) in a group of 14 patients with PD and 14 healthy controls (HC). Unlike the HC, who demonstrated significant inhibition in both tasks, the group with PD demonstrated intact inhibition only in the IOR task. Dopamine replacement therapy did not affect performance. The findings are discussed within the context of a model that differentiates the essential involvement of the basal ganglia for endogenously evoked spatial inhibition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mapping of semantic, phonological, and orthographic verbal working memory in normal adults with functional magnetic resonance imaging.

Twelve neurologically normal participants (4 men and 8 women) performed semantic, phonological, and orthographic working memory tasks and a control task during functional magnetic resonance imaging. Divergent regions of the posterior left hemisphere used for decoding and storage of information emerged in each working memory versus control task comparison. These regions were consistent with previous literature on processing mechanisms for semantic, phonological, and orthographic information. Further, working memory versus control task differences extended into the left frontal lobe, including premotor cortex, and even into subcortical structures. Findings were consistent with R. C. Martin and C. Romani's (1994) contention that different forms of verbal working memory exist and further suggest that a reconceptualization of premotor cortex functions is needed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Ground-based passive microwave remote sensing observations of soilmoisture at S-band and L-band with insight into measurementaccuracy

A ground-based experiment in passive microwave remote sensing of soil moisture was conducted in Huntsville, AL, from July 1-14, 1996. The goal of the experiment was to evaluate the overall performance of an empirically-based retrieval algorithm at S-band and L-band under a different set of conditions and to characterize the site-specific accuracy inherent within the technique. With high temporal frequency observations at S-band and L-band, the authors were able to observe large scale moisture changes following irrigation and rainfall events, as well as diurnal behavior of surface moisture among three plots, one bare, one covered with short grass and another covered with alfalfa. The L-band emitting depth was determined to be on the order of 0-3 or 0-5 cm below 0.30 cm³/cm³ with an indication that it is less at higher moisture values. The S-band emitting depth was not readily distinguishable from L-band. The uncertainty in remotely sensed soil moisture observations due to surface heterogeneity and temporal variability in variables and parameters was characterized by imposing random errors on the most sensitive variables and parameters and computing the confidence limits on the observations. Discrepancies between remotely sensed and gravimetric soil moisture estimates appear to be larger than those expected from errors in variable and parameter estimation. This would suggest that a vegetation correction procedure based on more dynamic modeling may be required to improve the accuracy of remotely sensed soil moisture     

Effects of noise on optimal deconvolution accuracy in microwave observations

Due to large footprints of remotely sensed microwave brightness temperatures, accuracy of microwave observations in areas of large surface heterogeneity has always been a technological challenge. Microwave observations in areas dominated by waterbodies typically exhibit observed brightness temperature several tens of kelvins lower than areas having no surface water. The non-linearity between brightness temperature and other geophysical quantities such as soil moisture makes the accuracy of microwave observations a critical element for accurate estimation of these quantities. In retrieving soil moisture estimates, an error of 1 K in remotely sensed microwave brightness temperatures results in about 0.5–1% error in volumetric soil moisture. Large uncertainties in the observed brightness temperatures make such observations unusable in areas of large brightness temperature contrast. In this article, we discuss a deconvolution method to improve accuracy using the overlap in the adjacent microwave observations. We have shown that the method results in improved accuracy of 40% in brightness temperature estimation in regions of high brightness temperature contrast.