Central Deficits Research Articles

Neurocognitive performance of a community-based sample of young people at putative ultra high risk for psychosis: Support for the processing speed hypothesis

Introduction. A wide variety of neurocognitive deficits have been reported for help-seeking individuals who are at clinical or ultra high risk for psychosis based on fulfilling set criteria for prodromal syndromes/at risk mental states. We wished to extend this research by conducting the first population-based assessment of prodromal syndromes and associated neurocognition. Methods. A sample of 212 school-based adolescents were assessed for prodromal syndromes using the criteria of prodromal syndromes from the Structured Interview for Prodromal Syndromes. The MATRICS consensus neurocognitive battery was used to assess cognitive functioning in this sample. Results. A total of 8% of the population sample of adolescents met criteria for a prodromal syndrome. These adolescents performed significantly more poorly than controls on two tests of processing speed—Trail-Making Test Part A, F=4.54, p < .01, and the Brief Assessment of Cognition in Schizophrenia Symbol Coding task, F=8.26, p < .0001—and on a test of nonverbal working memory—the Wechsler Memory Scale Spatial Span task, F=3.29, p < .05. Conclusions. Adolescents in the community who fulfil criteria for prodromal syndromes demonstrate deficits on a number of neurocognitive tasks. Deficits are particularly pronounced in symbol coding performance, supporting processing speed as a central deficit associated with psychosis risk.

Working memory deficits in Math learning difficulties: a meta-analysis

In the present study, we made a quantitative synthesis of the literature comparing children with Math learning difficulties to average-achieving, age-matched children on measures of working memory in view of Baddeley and Hitch’s multicomponential working memory model. Our meta-analytic investigation drew from the literature a number of 18 studies that matched the inclusion criteria. We hypothesized that all three components of Baddeley and Hitch’s model should contribute to the poor Math performance displayed by children with Math learning difficulties, and that this relation varies as a function of age. Also, we hypothesized that children with Math learning difficulties would present more accentuated working memory deficits for numerical material and/or processing. Based upon Cohen’s criteria, the results indicate a large effect size, in favor of the controls for the relationship between Math performance and central executive component, as well as Math performance and the visual–spatial sketchpad, more accentuated in younger ages. Only a moderate effect size emerged in the case of Math performance and the phonological loop (PL). With respect to numerical versus non-numerical working memory deficits, a large effect size emerged for numerical central executive measures, along with a moderate effect size for the PL numerical measures, and a weak effect size for non-numerical PL. The results indicate that Math difficulties are attributable to a central executive deficit or delay, more accentuated for numerical stimuli and/or processing and to a visual–spatial working memory deficit.

Similar alterations in brain function for phonological and semantic processing to visual characters in Chinese dyslexia

Dyslexia in alphabetic languages has been extensively investigated and suggests a central deficit in orthography to phonology mapping in the left hemisphere. Compared to dyslexia in alphabetic languages, the central deficit for Chinese dyslexia is still unclear. Because of the logographic nature of Chinese characters, some have suggested that Chinese dyslexia should have larger deficits in the semantic system. To investigate this, Chinese children with reading disability (RD) were compared to typically developing (TD) children using functional magnetic resonance imaging (fMRI) on a rhyming judgment task and on a semantic association judgment task. RD children showed less activation for both tasks in right visual (BA18, 19) and left occipito-temporal cortex (BA 37), suggesting a deficit in visuo-orthographic processing. RD children also showed less activation for both tasks in left inferior frontal gyrus (BA44), which additionally showed significant correlations with activation of bilateral visuo-orthographic regions in the RD group, suggesting that the abnormalities in frontal cortex and in posterior visuo-orthographic regions may reflect a deficit in the connection between brain regions. Analyses failed to reveal larger differences between groups for the semantic compared to the rhyming task, suggesting that Chinese dyslexia is similarly impaired in the access to phonology and to semantics from the visual orthography.

Cerebral Hydatid Cyst with Vestibular and Neurologic Manifestations

The authors present a case of intracranial hydatid cyst with rare neuro-otological manifestations as central vestibular syndrome and massive neurologic deficit. Computed tomography scan showed clearly the location of the cyst. Surgery was applied to remove the cyst. Albendazole used after surgery to improve patient’s prognosis. No such cases were reported before in Yemen to the best of our knowledge, however, cases of epilepsy are not rare but not well investigated. Vestibular dysfunction associated with intracranial hydatid cyst infection is not reported to date. Conclusion: There is no formal consensus for the medical treatment of hydatid cyst whether intracranial or elsewhere. The aim of treatment is to remove the cyst without causing any damage to the tissues occupied by the cyst or make any spillages to avoid anaphylactic shock or recurrence.

Emerging Perspectives Related to Quadriceps Central Activation Deficits in Patients with Total Knee Arthroplasty

Emerging Perspectives Related to Quadriceps Central Activation Deficits in Patients with Total Knee Arthroplasty

SELF-PSYCHOLOGICAL TREATMENT OF A SEX ADDICT WITH SADOMASOCHISTIC BEHAVIOURS: A CASE REPORT

From a self-psychological perspective, sex addiction can be viewed as repeated unsuccessful attempts at remedying central deficits in an uncohesive psychic structure. The sex addict uses sex in an attempt to compensate for the deficits in the self's capacities for tension regulation, self-soothing and self-esteem regulation, as well as, preventing regressive fragmentation. Until these psychic structures can be built for the sex addict, these deficits will continue to be disabling. A case formulation exemplifies some of the foundations upon which the self-psychology is used in conceptualizing a client's narcissism, hypochondria and sadomasochistic behaviour.

Normal hearing is not enough to guarantee robust encoding of suprathreshold features important in everyday communication

"Normal hearing" is typically defined by threshold audibility, even though everyday communication relies on extracting key features of easily audible sound, not on sound detection. Anecdotally, many normal-hearing listeners report difficulty communicating in settings where there are competing sound sources, but the reasons for such difficulties are debated: Do these difficulties originate from deficits in cognitive processing, or differences in peripheral, sensory encoding? Here we show that listeners with clinically normal thresholds exhibit very large individual differences on a task requiring them to focus spatial selective auditory attention to understand one speech stream when there are similar, competing speech streams coming from other directions. These individual differences in selective auditory attention ability are unrelated to age, reading span (a measure of cognitive function), and minor differences in absolute hearing threshold; however, selective attention ability correlates with the ability to detect simple frequency modulation in a clearly audible tone. Importantly, we also find that selective attention performance correlates with physiological measures of how well the periodic, temporal structure of sounds above the threshold of audibility are encoded in early, subcortical portions of the auditory pathway. These results suggest that the fidelity of early sensory encoding of the temporal structure in suprathreshold sounds influences the ability to communicate in challenging settings. Tests like these may help tease apart how peripheral and central deficits contribute to communication impairments, ultimately leading to new approaches to combat the social isolation that often ensues.

Saccades and Vergence Performance in a Population of Children with Vertigo and Clinically Assessed Abnormal Vergence Capabilities

PurposeEarly studies reported some abnormalities in saccade and vergence eye movements in children with vertigo and vergence deficiencies. The purpose of this study was to further examine saccade and vergence performance in a population of 44 children (mean age: 12.3±1.6 years) with vertigo symptoms and with different levels of vergence abnormalities, as assessed by static orthoptic examination (near point of convergence, prism bar and cover-uncover test).MethodsThree groups were identified on the basis of the orthoptic tests: group 1 (n = 13) with vergence spasms and mildly perturbed orthoptic scores, group 2 (n = 14) with moderately perturbed orthoptic scores, and group 3 (n = 17) with severely perturbed orthoptic scores. Data were compared to those recorded from 28 healthy children of similar ages. Latency, accuracy and peak velocity of saccades and vergence movements were measured in two different conditions: gap (fixation offset 200 ms prior to target onset) and simultaneous paradigms. Binocular horizontal movements were recorded by a photoelectric device.ResultsGroup 2 of children with vergence abnormalities showed significantly longer latency than normal children in several types of eye movements recorded. For all three groups of children with vergence abnormalities, the gain was poor, particularly for vergence movement. The peak velocity values did not differ between the different groups of children examined.InterpretationEye movement measures together with static orthoptic evaluation allowed us to better identify children with vergence abnormalities based on their slow initiation of eye movements. Overall, these findings support the hypothesis of a central deficit in the programming and triggering of saccades and vergence in these children.

Neurological Substrate of Central Auditory Processing Deficits in Children

Neurological Substrate of Central Auditory Processing Deficits in Children

Monkeys Recall and Reproduce Simple Shapes from Memory

If you draw from memory a picture of the front of your childhood home, you will have demonstrated recall. You could also recognize this house upon seeing it. Unlike recognition, recall demonstrates memory for things that are not present. Recall is necessary for planning and imagining, and it can increase the flexibility of navigation, social behavior, and other cognitive skills. Without recall, memory is more limited to recognition of the immediate environment. Amnesic patients are impaired on recall tests [1, 2], and recall performance often declines with aging [3]. Despite its importance, we know relatively little about nonhuman animals' ability to recall information; we lack suitable recall tests for them and depend instead on recognition tests to measure nonhuman memory. Here we report that rhesus monkeys can recall simple shapes from memory and reproduce them on a touchscreen. As in humans [4, 5], monkeys remembered less in recall than recognition tests, and their recall performance deteriorated more slowly. Transfer tests showed that monkeys used a flexible memory mechanism rather than memorizing specific actions for each shape. Observation of recall in Old World monkeys suggests that it has been adaptive for over 30 million years [6] and does not depend on language.

The Structure of Public Sector Debt in Brazil

The literature on the end of remarkable inflationary processes (Bresciani-Turroni, 1937; Sargent, 1986) calls our attention to one of the favorable aspects of hyperinflations: the fact that high inflation destroys old debts. Because of the central role fiscal deficits play in chronic inflation, the alleviation of the debt burden helps stabilization, and the fact that a large portion of government debt may disappear without the undesirable reputation costs of explicit debt repudiation is even better. In the Brazilian inflationary experience, most of this potentially favorable effect of high inflation on debt has been neutralized by indexation. In December 1994, officially recognized total federal domestic debt was 19. 9% of GDP. The fast growth of public debt in the first four years of stabilization has offset the benefits of the inflation acceleration, which occurred shortly before the onset of monetary reform in July, 1994. By December 1998, this figure was 44. 8% of GDP.

The importance of accurate visual assessment after stroke

Visual impairment is a common consequence of stroke. The purpose of this article is to briefly outline the prevalence of visual impairment following stroke, the different types of visual impairment and rehabilitation options. Visual impairment occurs in up to 70% of stroke survivors and may take the form of eye-movement deficits, loss of field-of-vision, central vis ual acuity impairment or cognitive visual perceptual deficits. These may also occur in combination. Rehabilitation options may be restitutive, compensatory or substitutive. The impact of visual impairment is wide ranging, affecting activities during the course of daily life leading to impaired quality of life, depression, isola

European Union: unification and convergence

As we embark on the tenth anniversary of the first introduction of the euro, it is befitting to take a step back and ask ourselves: have the economies achieved their economic goals set forth in the Maastricht Treaty and reaffirmed in the Treaties of Rome and Accession? Have they achieved economic convergence that was to be assured with the onset of the EU? This paper divides 30 European countries into 4 subgroups and assesses whether the groups have experienced a change in their overall and respective economic convergence rates. Per capita GDP, real-interest rate, lending interest rate, inflation rate, central government debt and deficit are analysed for evidence of convergence. The findings provide mixed results; rates of convergence vary by country and between the four subgroups. The study confirms that most countries have made progress towards convergence, however, convergence rates among and within subgroups are not in sync.

A LARGE NUMBER OFz&gt; 6 GALAXIES AROUND A QSO ATz= 6.43: EVIDENCE FOR A PROTOCLUSTER?

QSOs have been thought to be important for tracing highly biased regions in the early universe, from which the present-day massive galaxies and galaxy clusters formed. While overdensities of star-forming galaxies have been found around QSOs at 2<z<5, the case for excess galaxy clustering around QSOs at z>6 is less clear. Previous studies with HST have reported the detection of small excesses of faint dropout galaxies in some QSO fields, but these surveys probed a relatively small region surrounding the QSOs. To overcome this problem, we have observed the most distant QSO at z=6.4 using the large field of view of the Suprime-Cam (34' x 27'). Newly-installed CCDs allowed us to select Lyman break galaxies (LBG) at z~6.4 more efficiently. We found seven LBGs in the QSO field, whereas only one exists in a comparison field. The significance of this apparent excess is difficult to quantify without spectroscopic confirmation and additional control fields. The Poisson probability to find seven objects when one expects four is ~10%, while the probability to find seven objects in one field and only one in the other is less than 0.4%, suggesting that the QSO field is significantly overdense relative to the control field. We find some evidence that the LBGs are distributed in a ring-like shape centered on the QSO with a radius of ~3 Mpc. There are no candidate LBGs within 2 Mpc from the QSO, i.e., galaxies are clustered around the QSO but appear to avoid the very center. These results suggest that the QSO is embedded in an overdense region when defined on a sufficiently large scale. This suggests that the QSO was indeed born in a massive halo. The central deficit of galaxies may indicate that (1) the strong UV radiation from the QSO suppressed galaxy formation in its vicinity, or (2) that star-formation closest to the QSO occurs mostly in an obscured mode that is missed by our UV selection.

Large Intracranial Intradural Mucocele as a Complication of Frontal Sinus Osteoma

Paranasal sinus osteomas are mostly asymptomatic; however, secondary mucocele can develop if they impede the natural sinus drainage. Such a mucocele can destroy the bone and extend into the adjacent structures. We report on an unusual case of frontal sinus osteoma in a 27-year-old patient, complicated by large secondary mucocele that eroded the bone and extended into the frontal lobe of the brain. Unexpectedly, the patient did not report any visual or other symptoms attributable to central nervous system deficit. The mucocele was completely resected through bifrontobasal osteoplastic craniotomy, whereas osteoma was evacuated in its entirety by both drilling and mobilizing. Open surgical approach remains the main treatment for complicated paranasal sinus osteoma, and radical removal of intracranial mucocele is mandatory to prevent the development of life-threatening infections. Although intradural extension of a secondary mucocele is extremely unusual, head and neck surgery specialists should take this severe complication in consideration.

From governmental accounting to national accounting: implications on the Portuguese central government deficit

Based on the relevant differences between Governmental Accounting (GA/microeconomic perspective) and National Accounting (NA/macroeconomic perspective) this paper examines the main adjustments made in Portugal to the General Government Sector data required to convert Governmental Accounts into National Accounts. It also assesses the impact of those adjustments on the Central Government deficit, the largest share in the Portuguese public deficit.Following mostly a qualitative research methodology, the empirical study is based on interviews to officials preparing NA and on several documental sources. The purpose is to validate the major data adjustments from GA into NA regarding Central Government, while, in addition, assessing their impact using data from April 2008 Excessive Deficit Procedure notification, covering the 2004-2007 period. The main findings indicate that differences concerning the accounting basis are the most relevant and that the subsequent adjustments have a considerable impact on the Portuguese Central Government deficit. This research points therefore to the need for more convergence between GA and NA, namely with respect to the transactions recognition criteria in order to use a common accounting basis, and for a complete and coherent reporting information system in GA.

Attenuated baroreflex control of sympathetic nerve activity in obese Zucker rats by central mechanisms

Adult obese Zucker rats (OZRs) have reduced sympathetic responses to evoked changes in arterial pressure (AP) compared to lean Zucker rats (LZRs). This study examined whether attenuated sympathetic baroreflexes in OZRs may be due to altered sensory or central mechanisms. The OZRs had elevated baseline splanchnic sympathetic nerve activity (SNA) and mean AP (MAP) compared to age-matched LZRs under urethane anaesthesia (P < 0.05). Aortic depressor nerve activity (ADNA) was measured while AP was altered by infusions of phenylephrine or nitroprusside (+/-60 mmHg over 60-90 s) in rats treated with atropine and propranolol to eliminate changes in heart rate. Although baseline ADNA was higher in the hypertensive OZRs, the relationship between MAP and ADNA was comparable in OZRs and LZRs. In contrast, electrical stimulation of the ADN afferent fibres (5 s train, 2 ms pulses, 4 V, 0.5-48 Hz) produced dramatically smaller reductions in SNA and MAP in OZRs compared to LZRs (P < 0.05). After blockade of alpha-adrenergic receptors to prevent sympathetically mediated depressor responses, OZRs still had reduced sympathetic responses to stimulation of the ADN. In addition, stimulation of vagal afferent nerves electrically or with phenylbiguanide (1, 2, 4 and 8 microg, i.v.) produced smaller inhibitions of SNA in OZRs compared with LZRs (P < 0.05). These data suggest that attenuated sympathetic baroreflexes are the result of altered central mechanisms in OZRs, and not deficits in the responsiveness of aortic baroreceptors to AP. Furthermore, central deficits in the regulation of SNA in OZRs extend to other sympathoinhibitory reflexes initiated by vagal afferent nerves.

The attentional blink and lag 1 sparing are nonspatial

The attentional blink (AB) refers to the finding that the perception of the second of two targets (T2) is impaired when presented in close temporal proximity to the first target (T1). An exception to this deficit occurs when T2 immediately follows T1, an effect referred to as lag 1 sparing. So far, it has been unclear whether the AB is location specific or nonspatial in nature. Most demonstrations of an AB across different locations have shown an absence of lag 1 sparing, due to accompanying spatial switch costs. This means that the AB pattern itself may be explained through such switch costs. In this study, to minimize spatial switch costs, attention was made to move continuously across multiple locations by aid of a cue. An AB across different locations was found, including lag 1 sparing. We conclude that the AB and lag 1 sparing are not tied to a location but represent a central deficit, in line with current theory.

Sexual dimorphism of spatial working memory profiles in schizophrenia

Introduction. The aim of the present study was to compare spatial working memory performance of females and males schizophrenia patients to verify whether the sexual dimorphism of spatial abilities present in the general population is found also in schizophrenia. Methods. We analysed different types of errors committed by each gender on the spatial working memory test of the Cambridge Neuropsychological Test Automated Battery to determine potential differences between them. Results. Despite the lack of difference in the number of errors between men and women, different profiles of errors were associated with the strategy used according to gender. The men's strategy was better compared to women. Specifically, for women strategy score correlated positively with searches in previously visited boxes, whereas for men it correlated with both previously visited boxes and never visited ones. However, men's strategy is more impaired by the number of revisits in boxes in which tokens have previously been found than female's one. Conclusions. These results suggested impaired either central executive and/or visuospatial sketchpad of working memory in patients with schizophrenia. We demonstrated also that the worsening of strategy in men is principally due to central executive deficits compared to women with schizophrenia. The study of sex differences in cognitive performances could help in delineating partially different endophenotypes of schizophrenia in men and women.

Central Sensory-Motor Deficit After Uneventful Single-Dose Spinal Morphine Administration in a Patient with Preexisting Migraine Headaches

Hemiplegic migraine is a condition associated with vascular alteration of the central nervous system and transient neurologic deficits. Permanent morphine-induced motor dysfunction has been reported after spinal ischemia. We report a persisting central neurological deficit after single-dose spinal administration of 400 microg of morphine in a patient with no previous neurological condition. Hemiplegic migraine was thought to be present when the patient emerged from anesthesia. Weakness in the left quadriceps and saddle anesthesia of the perineum and urinary retention of central origin remained present 3 yr later. Over the 3 postoperative years, the patient was admitted to a neurological unit 5 times because of acute headache associated with complete left-sided hemiplegia. These symptoms resolved within 24 h of onset. Hemiplegic migraine was thought to be the most likely diagnosis of these recurrent attacks. We hypothesize that the patient's persistent deficits were caused by a combination of spinal morphine and spinal cord vascular dysfunction associated with hemiplegic migraine.