Time as a guide to cause.

How do people learn causal structure? In 2 studies, the authors investigated the interplay between temporal-order, intervention, and covariational cues. In Study 1, temporal order overrode covariation information, leading to spurious causal inferences when the temporal cues were misleading. In Study 2, both temporal order and intervention contributed to accurate causal inference well beyond that achievable through covariational data alone. Together, the studies show that people use both temporal-order and interventional cues to infer causal structure and that these cues dominate the available statistical information. A hypothesis-driven account of learning is endorsed, whereby people use cues such as temporal order to generate initial models and then test these models against the incoming covariational data. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

It is time to reconsider the Graduate Record Examination.

Reviews the generally low correlations of graduate record examination (gre) general aptitude scores with various criteria of performance in graduate school. A retrospective study of phd's from 1 university is also reported, relating gre scores to postdoctoral publication records. Correlations were statistically zero (.02-.24), computed in several ways for both clinical and nonclinical graduates. A national review of the use of the gre for screening is suggested in light of its apparent effectiveness as an obstacle for the admission of minority students. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Management of the mitochondrial encephalopathies

INTRODUCTION: In the management of mitochondrial diseases, it is most important to know what mitochondrias are, how they function and the pattern of inheritance present on the different conditions affecting them. DEVELOPMENT: An overview of mitochondrial function, inheritance, clinical and biochemical classification is done, reviewing the different fatty acid oxidation, pyruvic metabolism and respiratory chain defects. Classification by age of onset is also done. Approach to diagnosis, clinical aspects, laboratory findings and available treatment is discussed. Some comments about the use of a neurometabolic database are discussed, where more than 150 conditions are described in detail. CONCLUSIONS: By using the search capabilities of the software, a search by age of onset, symptoms, signs and laboratory findings help in reaching the most probable diagnosis in a given child, with its recommended current management.     

Rejoinder to Weitzman's comments on "It is time to reconsider the GRE."

In response to R. A. Weitzman's (1972) comments on A. R. Marston's (see record 1972-11620-001) article on the Graduate Record Examination (GRE), Marston notes that the GRE is an unvalidated test that affects many thousands of lives. Psychologists cannot blame the Educational Testing Service (ETS) for its position that the GRE is not designed to predict performance in professional life if psychology does not provide the ETS with appropriate criteria for them to predict. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

NICE, a new cause of death classification for stillbirths and neonatal deaths. Neonatal and Intrauterine Death Classification according to Etiology

During May 1996, field surveys on Lyme disease spirochetes were conducted in Beijing, Shenyang, Fushun, and Inner Mongolia in northeastern China. The ticks collected consisted of 3 genera and 12 species. Of these, Ixodes persulcatus was dominant in sun-exposed vegetation in forests in Inner Mongolia; 57 Borrelia strains (55/123 unfed adults and 2/5 immature stages fed on a rodent) were obtained from this tick by BSK culture. Additionally, 2/2 Apodemus peninsulae were positive. Ixodes nipponensis, Ixodes pavlovskyi, Haemaphysalis douglasi, and Haemaphysalis megaspinosa, newly recorded in China, and other Haemaphysalis spp. were all negative for Borrelia. Based on a polymerase chain reaction restriction fragment length polymorphism analysis of the 45 strains successfully subcultured, these were classified as 29 Borrelia garinii and 16 Borrelia afelii. These strains seemed to be more closely related to Japanese strains in genetic features than to those from Europe. The result of sodium dodecyl sulfate-polyacrylamide gel electrophoresis suggested more diversity in both genospecies, but Borrelia burgdorferi sensu stricto was not found.     

Time course of the blindness to response-compatible stimuli.

This article examines the time course of a deficit in identifying a stimulus sharing a compatible feature with a response that is executed in parallel ("blindness to response-compatible stimuli," J. Müsseler & B. Hommel, 1997a). In 5 experiments, participants performed a timed response, and the presentation point of time of a to-be-identified stimulus was varied in respect to response execution. A blindness effect was observed when the stimulus was presented between response cue offset and response execution. In contrast, the identification of a stimulus presented before the response cue or after response execution was not affected by stimulus-response compatibility—a finding that rules out a retention-based explanation. These results support an explanation that states that the perceptual processing of a stimulus feature is impaired as long as the shared perception–action feature code is integrated into the representation of a to-be-executed response. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Therapeutical approaches to transmissible spongiform encephalopathies (TSE): the case of amphotericin-B

Within 1987-1995 the authors observed 16 cases of tuberculosis in HIV-infected patients which accounted for 26.7% of AIDS patients treated by them. 14 cases were diagnosed intravitally, 2 postmortem. Infiltrative, generalized, cavernous, intrathoracic lymph node, intraabdominal lymph node tuberculosis and tuberculous pleurisy were identified in 5, 6, 2, 1, 1 and 1 patients, respectively. 6 patients from the above are still alive and are receiving treatment (5 of them with infiltrative tuberculosis), 10 died. Tuberculosis course and outcomes in HIV-infected subjects depended on the stage of their immunodeficiency. In moderate immunodeficiency (CD4-lymphocyte > 200/mm3) tuberculosis ran, as a rule, as local and infiltrative, sensitive to specific therapy. In severe damage to immune system (CD4 < 100/mm3) tuberculosis acquired a generalized course, sometimes fulminant, resistant to treatment. It is inferred that HIV-infected subjects with immunodeficiency need tuberculosis prophylaxis with isoniazide or rifampicin.     

Neuropathology of spongiform encephalopathies in humans

The historical aspects and classification of human spongiform encephalopathies are reviewed and the newer concept of 'prion dementias' is explored. Guidelines for safe laboratory and autopsy handling of spongiform encephalopathy tissues are outlined: this includes an update on strategies which are currently thought to be effective in decontamination. A wide ranging review of the pathology of the various human spongiform encephalopathies includes newly emerging data on microglia, and cell-specific and neurodegenerative proteins. A large section of this chapter is devoted to the methodology of immunocytochemical demonstration of PrP in tissue sections, and the dilemmas inherent in interpretation. Clinicopathological correlations are provided for classical cases of spongiform encephalopathy, together with the newly recognised atypical dementias associated with PrP gene mutations. The pathology of iatrogenic cases of CJD is described. The chapter concludes with problems in differential diagnosis, and discussion of the histopathological features which help to resolve diagnostic dilemmas.     

Neonatal habituation and dishabituation to tactile stimulation during sleep.

Two experiments examined habituation and dishabituation of behavioral responding to repeated presentations of a tactile stimulus (brush stroke) in 48 newborns during the 1st epoch of active-quiet sleep following a feeding. Exp I demonstrated habituation to a repeatedly presented brush stroke to the ear but failed to demonstrate dishabituation (i.e., response recovery) to the original brush stroke following an intense auditory stimulus (86 dB rattle sound). A post hoc control group showed that the intense auditory stimulus had suppressed subsequent responding to the tactile stimulus. Exp II replicated the habituation phase of Exp I and demonstrated response recovery to stimulation at a novel tactile site and to an auditory probe. Results indicate that the habituation paradigm used in infancy research could be successfully extended to the tactile modality. It is also suggested that prior auditory stimulation, but not prior tactile stimulation, might direct attention away from a subsequently presented tactile stimulus. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Encephalitis. Identifying the specific cause is key to effective management

Acute viral encephalitis and postinfectious encephalomyelitis affect both children and adults. Enteroviruses, HSV types 1 and 2, and arboviruses are the most common causes of encephalitis in the United States; however, the differential diagnosis is broad. History taking and physical examination can provide clues to the cause, but the diagnosis is usually established on the basis of CSF analysis, viral culture, MRI, and serologic testing, when indicated. In the future, PCR techniques may enhance rapidity of diagnosis. Until the specific cause is identified, empirical therapy should be given. Because complications can be severe, all patients with encephalitis should be monitored in a facility capable of providing supportive intensive care. Long-term follow-up is important to detect sequelae, particularly in patients with eastern equine or HSV encephalitis.     

Bismuth myoclonic encephalopathies. Their course and lasting or definitive late complications

Acute myoclonic encephalopathy related to the ingestion of bismuth salts has been known for 3 years and would appear to be reversible. Of a total of 41 cases, 32 were observed for an average of more than a year. Alongside the commoner benign forms, there coexist severe forms, sometimes fatal, prolonged forms and complicated forms. Permanent deterioration, affecting memory above all, tremor, marked insomnia, headache and disturbed gait are amongst the most durable complications, sometimes definitive, whilst in four cases osteo-arthropathy of the shoulders was associated with permanent invalidism.     

Neonatal precursors of infant behavior.

Tested 92 clinically normal infants (48 male, 44 female) at 2 and 90 days of age. At 2 days, they were tested in the hospitals in which they were born. Five hours of autonomic recordings during undisturbed periods and 1 hr of behavioral testing yielded measures that when factor analyzed produced 3 stable dimensions: Reactivity-Irritability, Maturity, and Reflexive and Discriminative Sucking. These dimensions were related to observational data obtained from the infants at 90 days of age. At 90 days, 2 home visits totaling 12 hrs yielded behavioral observations and ratings that when factor analyzed yielded 3 dimensions for males (Tonic-Active, Social, and Clarity) and 4 for females (Active-Social, Tonic, Positive Vocalizations, and Clarity). Correlations between the newborn factors and those obtained at 90 days revealed 1 summarizing relation for males: Newborn Maturity was positively correlated with Tonic-Active behavior at 90 days. No relations were found for females. Results reflect the greater endogenous stability for males and support hypotheses that females may be more receptive to environmental influence during early infancy. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neonatal exposure to cocaine enhances the reward-potentiating properties of the drug in young adult animals.

Either cocaine (20 mg/kg) or saline vehicle was administered to rat pups once daily on postnatal days 1–8. The enhancement of braid stimulation reward (BSR) by acute administration of cocaine (2.5, 5, and 10 mg/kg ip) was assessed in adult offspring (70–90 days of age) using a rate-frequency curve-shift paradigm. Acute administration of cocaine produced orderly dose-related shifts of the rate-frequency function toward lower frequencies in all groups indicating a reward-enhancing effect of the drug on BSR. However, offspring neonatally exposed to cocaine displayed a greater drug-induced potentiation of BSR. Of particular note, the small but significant enhancement of the reward-potentiating properties of cocaine was more pronounced in female offspring neonatally exposed to the drug. These findings indicate that the rewarding properties of cocaine were altered by neonatal exposure to the drug in a sexually dimorphic fashion. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The evolution of views on the nosological position of transmissible spongiform encephalopathies

We report here on the evolution of view on the nature of transmissible spongiform encephalopathies or prion disease. While the nosological position of these diseases is well understood, the nature of the agent is still a matter of dispute. There is no doubt, however, that the gene for PrP plays a major role in the whole group of neurodegenerations.     

Diagnosis of Creutzfeldt-Jakob disease and related human spongiform encephalopathies

Spongiform encephalopathies are transmissible diseases (TSE) of animals and humans. With the appearance of bovine spongiform encephalopathy (BSE) in 1986 and in 1996 with the identification of an apparently new variant of the human spongiform encephalopathy Creutzfeldt-Jakob disease (CJD), great concerns of a potential transmission of BSE to humans have been voiced. The agent known to transmit CJD and other human and animal spongiform encephalopathies is designated as prion, i.e., proteinaceous infectious agent, due to the absence of evidence for the involvement of a nucleic acid in disease transmission. In humans the clinical diagnosis of typical CJD cases can now be supported by paraclinical parameters. Electroencephalographic changes, so called periodic sharp wave complexes, are pathognomonic for CJD but by no means specific. The detection of neuronal enzymes in the cerebrospinal fluid (CSF) such as neuron specific enolase (NSE) or glial proteins such as S-100 aids greatly in the diagnosis of a human spongiform encephalopathy. By far the most specific marker in CSF are a group of proteins designated 14-3-3. Current evidence suggests that by including elevated levels of NSE (> or = 35 ng/mL), S-100 (> or = 8 ng/mL) and tau protein in the CSF and the presence of 14-3-3, a laboratory supported diagnosis of CJD can be achieved which in the appropriate clinical setting has a better diagnostic accuracy than the currently used clinical and paraclinical diagnostic criteria alone.     

The use of transgenic mice in the investigation of transmissible spongiform encephalopathies

The prion, the transmissible agent that causes spongiform encephalopathies such as scrapie, bovine spongiform encephalopathy and Creutzfeldt-Jakob disease, is believed to be devoid of nucleic acid and to be identical to PrPSc (prion protein: scrapie form), a modified form of the normal host protein PrPC (prion protein: cellular form) which is encoded by the single copy gene Prnp. The 'protein only' hypothesis proposes that PrPSc, when introduced into a normal host, causes the conversion of PrPC into PrPSc; it therefore predicts that an animal devoid of PrPC should be resistant to prion diseases. The authors generated homozygous Prnp(o/o) ('PrP knockout') mice and showed that, after inoculation with prions, these mice remained free from scrapie for at least two years while wild-type controls all died within six months. There was no propagation of prions in the Prnp(o/o) animals. Surprisingly, heterozygous Prnp(o/+) mice, which express PrPC at about half the normal level, also showed enhanced resistance to scrapie despite high levels of infectious agent and PrPSc in the brain at an early stage. After introduction of murine PrP transgenes, Prnp(o/o) mice became highly susceptible to mouse--but not to hamster--prions, while the insertion of Syrian hamster PrP transgenes rendered the mice susceptible to hamster prions but much less susceptible to mouse prions. These complementation experiments enabled the application of reverse genetics. The authors prepared animals transgenic for genes encoding PrP with amino terminal deletions of various lengths and found that PrP that lacks 48 amino proximal amino acids (which comprise four of the five octa repeats of PrP) is still biologically active.