Implicit measures of association in psychopathology research.

Studies obtaining implicit measures of associations in Diagnostic and Statistical Manual of Mental Disorders (4th ed., Text Revision; American Psychiatric Association, 2000) Axis I psychopathology are organized into three categories: (a) studies comparing groups having a disorder with controls, (b) experimental validity studies, and (c) incremental and predictive validity studies. In the first category, implicit measures of disorder-relevant associations were consistent with explicit beliefs for some disorders (e.g., specific phobia), but for other disorders evidence was either mixed (e.g., panic disorder) or inconsistent with explicit beliefs (e.g., pain disorder). For substance use disorders and overeating, expected positive and unexpected negative associations with craved substances were found consistently. Contrary to expectation, implicit measures of self-esteem were consistently positive for patients with depressive disorder, social phobia, and body dysmorphic disorder. In the second category, short-term manipulations of disorder-relevant states generally affected implicit measures as expected. Therapeutic interventions affected implicit measures for one type of specific phobia, social phobia, and panic disorder, but not for alcohol use disorders or obesity. In the third category, implicit measures had predictive value for certain psychopathological behaviors, sometimes moderated by the availability of cognitive resources (e.g., for alcohol and food, only when cognitive resources were limited). The strengths of implicit measures include (a) converging evidence for dysfunctional beliefs regarding certain disorders and consistent new insights for other disorders and (b) prediction of some psychopathological behaviors that explicit measures cannot explain. Weaknesses include (a) that findings were inconsistent for some disorders, raising doubts about the validity of the measures, and (b) that understanding of the concept “implicit” is incomplete. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Phenylacetonitrile; an auxin-like growth substance from sugar beet (Beta vulgaris)

Steam distillates and ethyl acetate extracts of sugar beet leaves and roots contained an auxin-like substance that stimulated elongation of wheat-coleoptile sections, and whose mobility on paper chromatograms was similar to phenylacetonitrile. Gas chromatography-mass spectrometry detected and identified phenylacetonitrile, together with 11 other volatile constituents, from sugar beet leaves.     

The role of blood pressure and aldosterone in the production of hemorrhagic stroke in captopril-treated hypertensive rats

BACKGROUND AND PURPOSE: We tested the hypothesis that the lowering of plasma aldosterone levels contributed to the antistroke effects of captopril treatment in Wistar Kyoto stroke-prone spontaneously hypertensive rats (SHRSP). METHODS: The suppression of plasma aldosterone by captopril treatment (50 mg.kg-1.d-1) was prevented by the subcutaneous infusion of aldosterone into captopril-treated SHRSP. We studied the effect this had on blood pressure (BP) and stroke development. RESULTS: SHRSP fed a Japanese-style diet containing 4% NaCl developed hypertension and a 100% mortality associated with intracerebral hemorrhage by 14 weeks of age. Captopril treatment from 6 weeks of age did not lower the BP but increased survival past 35 weeks of age. Hydralazine treatment (40 to 80 mg/L of drinking water) lowered BP in SHRSP but was less effective than captopril in retarding stroke. Plasma aldosterone levels were elevated with age in SHRSP after 10 weeks and were higher in poststroke versus prestroke SHRSP. Captopril treatment suppressed plasma aldosterone. When we elevated plasma aldosterone in captopril-treated SHRSP to levels between those present in untreated pre- and poststroke SHRSP, the ability of captopril to retard stroke development was negated. The effects of aldosterone were mimicked by deoxycorticosterone (40 mg/kg, SC2 times/wk) but not by dexamethasone (0.1 mg.kg-1.d-1, SC). Spironolactone treatment (20 mg.kg-1.d-1, SC) of SHRSP reduced BP but had little effect on stroke development. CONCLUSION: Elevations in plasma aldosterone enhance stroke development within captopril-treated SHRSP through mechanisms that do not involve stimulation of mineralocorticoid receptors or the enhancement of hypertension. The antistroke effects of captopril treatment may be partially mediated through the suppression of plasma aldosterone.     

Volatiles of cooked cabbage

A simple but effective sampling technique was used to collect the flavour volatiles of cooking cabbage. Using gas chromatography 35 components were obtained and most of these were identified using relative retention data and mass spectrum evidence. The relative abundance of each volatile was calculated.     

Evaluation of sensitivity of 10 diagnostic assays for Chlamydia trachomatis by use of a simple laboratory procedure

AIMS: To determine the sensitivity of commercially available diagnostic assays for Chlamydia trachomatis using a simple method. METHODS: Nine commercial assays and an "in-house" polymerase chain reaction (PCR) were evaluated using serial dilutions of a laboratory grown H serovar--four of them using a laboratory grown E serovar. Seven of the assays were further tested using dilutions of several cervical samples known to contain chlamydiae. RESULTS: The most sensitive assays were the MicroTrak direct fluorescent antibody (DFA) test (Syva) and the PCR which detected C trachomatis at a 10(-8) dilution of the H serovar, while the two least sensitive, Clearview (Unipath) and TestPack (Abbott), were positive only at 10(-4) and 10(-3) dilutions, respectively. A range of enzyme immunoassays (EIAs) and a nucleic acid hybridisation test were of intermediate sensitivity. The results with serovar E were consistent with these. When clinical samples were examined, the DFA test detected C trachomatis in dilutions at least 10-fold greater than any other assay. CONCLUSIONS: The range of sensitivity of diagnostic assays determined by the laboratory dilution procedure is very wide. Sensitivity assessed in this way, however, reflects the ability of the assays to detect C trachomatis in large scale clinical trials. The dilution procedure, which is simple to undertake, could therefore be applied by any laboratory before a new diagnostic method is considered for routine use.     

Effects of negative and positive mood phrases on priming of alcohol words in young drinkers with high and low anxiety sensitivity.

This study investigated whether potential emotional cues for drinking activate alcohol concepts in young drinkers. Participants were 84 university freshmen with high or low levels of anxiety sensitivity (AS). A verbal priming task measured activation (i.e., priming) of alcohol concepts (e.g., beer) by positive and negative mood phrases. Time to read alcohol target words was the dependent measure. Negative mood phrases consistently primed alcohol targets; positive mood phrases did not. Degree of negative mood priming did not differ as a function of gender or AS. Reported tendency to drink in bad moods predicted negative mood priming in women, whereas men showed negative mood priming irrespective of their reported drinking tendency. A general association between negative mood priming and severity of alcohol problems also emerged. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

When learning met memory.

The first sentence of the introduction to Hebb's (1949) classic monograph, The organization of behavior, is “It might be argued that the task of the psychologist, the task of understanding behaviour and reducing the vagaries of human thought to a mechanical process of cause and effect, is a more difficult one than that of any other scientist” (p. xi). Nowhere is this more true than in the realm of human learning and memory, given our truly remarkable ability to acquire and retain prodigious amounts of information. This article is divided into two parts. The first part sketches my lifelong fascination with learning that led me to study first memory, then attention, and then their interplay, with examples of a few interesting findings along that path. The second part details recent work in my laboratory exploring a simple yet quite powerful encoding technique: Saying things aloud improves memory for them. This benefit, which we call the production effect, likely occurs by enhancing the distinctiveness of the things said aloud, and may constitute a beneficial study method. Understanding how we learn and remember is ultimately a crucial step in understanding ourselves. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Chromaticity diagram showing cone excitation by stimuli of equal luminance.

In a space where Cartesian coordinates represent the excitations of the three cone types involved in color vision, a plane of constant luminance provides a chromaticity diagram in which excitation of each cone type (at constant luminance) is represented by a linear scale (horizontal or vertical), and in which the center-of-gravity rule applies with weights proportional to luminance.