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Discrimination Test (discrimination + test)

Distribution by Scientific Domains

Medical Sciences	66%

Selected Abstracts

Normative data on Benton Visual Form Discrimination Test for older adults and impaired scores in Clinical Dementia Rating 0.5 participants: Community-based study.

PSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 1 2009
Tajiri Project, The Osaki
Aims:, The Benton Visual Form Discrimination test (VFD) is one of the non-verbal tests to assess the capacity for complex visual form discrimination. The purposes of the present study were to investigate the effects of age and education level of the VFD in healthy elderly subjects, rigorously excluding participants with Clinical Dementia Rating (CDR) 0.5, and the characteristics of VFD patterns in CDR 0.5 participants. Methods:, The 597 participants included CDR 0 (healthy elderly, n = 405), CDR 0.5 (mild cognitive impairment, n = 161), and CDR 1 and 2 (dementia, n = 31). The VFD, Digit Forwards, Digit Backwards and Rey,Osterrieth Complex Figure Test (RCFT) copying were used for neuropsychological assessment. Results:, There were significant effects of age and education level on the VFD in healthy participants, and the CDR 0.5 group had a lower score on the VFD than the healthy group. Low performance on the VFD was associated with Digit Backward and RCFT copying in both healthy and CDR 0.5 participants. Conclusions:, CDR 0.5 participants exhibit deficits of visual form discrimination related to attention, visual construction and organization. [source]

The relationship between history of violent and criminal behavior and recognition of facial expression of emotions in men with schizophrenia and schizoaffective disorder

AGGRESSIVE BEHAVIOR, Issue 3 2006
Elisabeth M. Weiss
Abstract Social psychological research underscores the relation between aggression and emotion. Specifically, regulating negative affect requires the ability to appraise restraint-producing cues, such as facial signs of anger, fear and other emotions. Individuals diagnosed with major mental disorders are more likely to have engaged in violent behavior than mentally healthy members of the same communities. We examined whether violent and criminal behavior in men with schizophrenia is related to emotion recognition abilities. Forty-one men with schizophrenia underwent a computerized emotion discrimination test presenting mild and extreme intensities of happy, sad, angry, fearful and neutral faces, balanced for gender and ethnicity. History of violence was assessed by the Life History of Aggression Scale and official records of arrests. Psychopathology was rated using the Positive and Negative Symptom Scale. Criminal behavior was associated with poor emotion recognition, especially for fearful and angry facial expressions. History of aggression was also associated with more severe positive symptoms and less severe negative symptoms. These findings suggest that misinterpretation of social cues such as angry and fearful expression may lead to a failure in socialization and adaptive behavior in response to emotional situation, which may result in a higher number of criminal arrests. Aggr. Behav. 32:1,8, 2006. © 2006 Wiley-Liss, Inc. [source]

Ethanol Attenuates Spatial Memory Deficits and Increases mGlu1a Receptor Expression in the Hippocampus of Rats Exposed to Prenatal Stress

ALCOHOLISM, Issue 8 2009
Vincent Van Waes
Background:, Although it is generally believed that chronic ethanol consumption impairs learning and memory, results obtained in experimental animals are not univocal, and there are conditions in which ethanol paradoxically improves cognitive functions. In the present work, we investigated the effects of prenatal stress and of chronic ethanol exposure during adulthood on spatial memory in rats. Methods:, Rats were subjected to a prenatal stress delivered as 3 daily 45-minute sections of restraint stress to the mothers during the last 10 days of pregnancy (PRS rats). After 7 months of ethanol exposure (ethanol 10%, oral intake), memory performances were evaluated in a spatial discrimination test in control and PRS male rats. Then, the oxidative damages and the expression of metabotropic glutamate (mGlu) receptors were assessed in their hippocampus. Results:, Chronic ethanol exposure resulted in a reduced performance in a spatial recognition task in control animals. Unexpectedly, however, the same treatment attenuated spatial memory deficits in rats that had been subjected to prenatal stress. This paradigm of ethanol administration did not produce detectable signs of oxidative damage in the hippocampus in either unstressed or PRS rats. Interestingly, ethanol intake resulted in differential effects in the expression of mGlu receptor subtypes implicated in mechanisms of learning and memory. In control rats, ethanol intake reduced mGlu2/3 and mGlu5 receptor levels in the hippocampus; in PRS rats, which exhibited a constitutive reduction in the levels of these mGlu receptor subtypes, ethanol increased the expression of mGlu1a receptors but did not change the expression of mGlu2/3 or mGlu5 receptors. Conclusion:, Our findings support the idea that stress-related events occurring before birth have long-lasting effects on brain function and behavior, and suggest that the impact of ethanol on cognition is not only dose- and duration-dependent, but also critically influenced by early life experiences. [source]

Effects of the Glucocorticoid Antagonist, Mifepristone, on the Consequences of Withdrawal From Long Term Alcohol Consumption

ALCOHOLISM, Issue 12 2008
Catherine Jacquot
Background:, Studies were carried out to test the hypothesis that administration of a glucocorticoid Type II receptor antagonist, mifepristone (RU38486), just prior to withdrawal from chronic alcohol treatment, would prevent the consequences of the alcohol consumption and withdrawal in mice. Materials and Methods:, The effects of administration of a single intraperitoneal dose of mifepristone were examined on alcohol withdrawal hyperexcitability. Memory deficits during the abstinence phase were measured using repeat exposure to the elevated plus maze, the object recognition test, and the odor habituation/discrimination test. Neurotoxicity in the hippocampus and prefrontal cortex was examined using NeuN staining. Results:, Mifepristone reduced, though did not prevent, the behavioral hyperexcitability seen in TO strain mice during the acute phase of alcohol withdrawal (4 hours to 8 hours after cessation of alcohol consumption) following chronic alcohol treatment via liquid diet. There were no alterations in anxiety-related behavior in these mice at 1 week into withdrawal, as measured using the elevated plus maze. However, changes in behavior during a second exposure to the elevated plus maze 1 week later were significantly reduced by the administration of mifepristone prior to withdrawal, indicating a reduction in the memory deficits caused by the chronic alcohol treatment and withdrawal. The object recognition test and the odor habituation and discrimination test were then used to measure memory deficits in more detail, at between 1 and 2 weeks after alcohol withdrawal in C57/BL10 strain mice given alcohol chronically via the drinking fluid. A single dose of mifepristone given at the time of alcohol withdrawal significantly reduced the memory deficits in both tests. NeuN staining showed no evidence of neuronal loss in either prefrontal cortex or hippocampus after withdrawal from chronic alcohol treatment. Conclusions:, The results suggest mifepristone may be of value in the treatment of alcoholics to reduce their cognitive deficits. [source]

Recovery of touch after median nerve lesion and subsequent repair

MICROSURGERY, Issue 1 2003
M.F. Meek M.D., Ph.D.
Many techniques have been developed for the evaluation of peripheral nerve function. Consequently, physicians use different techniques in the clinic. This study describes the evaluation of touch after median nerve lesions in the forearm and repair. In order to evaluate touch, 25 patients, aged 11,51 years (mean, 29 years), were evaluated 3,10.5 years (mean, 5 years) after median nerve repair. The evaluation included the moving two-point discrimination test and Semmes-Weinstein monofilaments. We showed that 32% good,excellent results can be obtained with difficult nerve lesions. The results could have been improved if a sensory reeducation regime had been applied. © 2003 Wiley-Liss, Inc. MICROSURGERY 23:2,5 2003 [source]

Extended testing across, not within, tasks raises diagnostic accuracy of smell testing in Parkinson's disease,

MOVEMENT DISORDERS, Issue 1 2009
Sanne Boesveldt MSc
Abstract The aim of this study was to determine whether extended olfactory testing within a single olfactory task and/or across olfactory tasks increases diagnostic accuracy of olfactory testing in Parkinson's disease (PD). Olfactory function was assessed using an extended version of the "Sniffin' Sticks", comprising 32-item odor identification and discrimination tasks, and a detection threshold task in 52 PD patients and 50 controls, all aged between 49 and 78 years. ROC curves based on sensitivity and specificity estimates were used to compare the diagnostic accuracy of extended and combined olfactory testing. There was no significant difference in diagnostic accuracy between the 16-item and the 32-item versions of the odor identification or discrimination test. The single olfactory test that was best in discriminating between PD patients and controls was a 16-item odor identification test. A combination of the 16-item identification test and the detection threshold task had a significantly higher area under the curve than the 16-item odor identification test alone. In conclusion, extended testing across, and not within, olfactory tasks increases diagnostic accuracy of olfactory testing in PD. A combination of an odor detection threshold task and a 16-item odor identification test had the highest sensitivity and specificity in distinguishing between PD patients and controls. © 2008 Movement Disorder Society [source]

N -methyl-1-(1,3-benzodioxol-5-yl)-2-butanamine (MBDB): its properties and possible risks

ADDICTION BIOLOGY, Issue 3 2000
L. A. G. J. M. Van Aerts
MBDB (N -methyl-1-(1,3-benzodioxol-5-yl)-2-aminobutane) is the ,-ethyl homologue of MDMA (3,4-methylenedioxy-N-methylamphetamine). MBDB is metabolized and excreted similarly to MDMA: presumably, the majority of oral MBDB is excreted in urine unmetabolized. The main metabolic routes in man are thought to be O-dealkylation and subsequent methylation, sulphation and glucuronidation of the newly formed hydroxy groups. The major acute neuropharmacological effects of MBDB in the rat are an increase in serotonin release in the brain and an inhibition of serotonin and noradrenaline re-uptake. These effects compare well with those of MDMA, although the latter is more potent. MBDB may also slightly increase dopamine release and inhibit dopamine re-uptake, but to a lesser extent than MDMA. This is important, as dopamine release has been implicated in the reinforcing qualities of substances such as cocaine and amphetamine. The neuroendocrine effects of MBDB resemble those of MDMA. Both substances increase plasma ACTH, corticosterone, prolactin and renin. The neurophysiological effects of MBDB are characterized by a decrease in electrical activity throughout the brain, most notably in the alpha 2 and delta frequency bands. In contrast, hallucinogens increase the activity in the alpha 1 band, especially in the corpus striatum. In drug discrimination tests in the rat, MBDB, like MDMA, can be distinguished clearly from both stimulants and hallucinogens. The class of substances to which MBDB belongs may be named entactogens. MBDB dose-dependently increases locomotor activity and decreases exploratory behaviour in the rat and causes distress vocalization and wing extension in the newly hatched chicken. The rewarding properties of MBDB appear to be smaller than those of MDMA, as suggested by a 2.5 times weaker potency in the conditioned place preference test in rats. The main subjective effects of MBDB in man are a pleasant state of introspection, with greatly facilitated interpersonal communication and a pronounced sense of empathy and compassion between subjects. In this respect, MBDB again resembles MDMA. However, there are also differences. MBDB has a slower and more gentle onset of action than MDMA, produces less euphoria and has less stimulant properties. The few toxicological data available suggest that MBDB may cause serotonergic deficits in the brain, although the potency of MBDB to cause this neurotoxic effect is smaller than that of MDMA. Severe acute reactions in man as have been reported for MDMA have not been published for MBDB. The dependence potential of MBDB appears to be small, probably even smaller than that of MDMA. MBDB has been available at least since 1994 but its position on the synthetic drugs market is marginal. Subjective reports indicate that MBDB is less popular among users than MDMA. The reason may be that MBDB produces less euphoria than MDMA. Another possible explanation is that MBDB largely lacks the stimulant properties of MDMA. We calculated a margin of safety with a method similar to one used in the risk assessment of pharmaceuticals. The results suggest that MBDB is three times less likely to cause serotonergic brain deficits than MDMA. However, it should be noted that for both substances the margin of safety is less than one, indicating that the risk of neurotoxicity is not negligible. In animals, serotonergic brain deficits after exposure to MDMA have been linked to the degeneration of serotonergic nerve terminals. [source]

THE SIGNAL DETECTION THEORY ROC CURVE: SOME APPLICATIONS IN FOOD SENSORY SCIENCE

JOURNAL OF SENSORY STUDIES, Issue 2 2008
M. O'MAHONY
ABSTRACT In psychology, the receiver operating characteristic (ROC) curve is a key part of Signal Detection Theory, which is used for calculating d, values in discrimination tests. In food sensory science, the ROC curve can also be a useful tool. To give a specific example, it is not always convenient to use forced-choice protocols for difference tests; foods may be fatiguing, and assessments with single presentations, like the Yes,No procedure, might be more appropriate. In this case, ROC curves provide a useful method for computing d, values. More generally, ROC curves give information about cognitive strategies. Cognitive strategies are important for difference tests. Values of d, can only be computed if the cognitive strategy used in the test is known. PRACTICAL APPLICATIONS When using methods other than two-alternative forced-choice in difference testing, a receiver operating characteristic (ROC) curve would be required to compute d,. This is because when assessing discrimination ability, the cognitive strategy of the subject must be taken into account, and ROC curves can sometimes reveal the cognitive strategy used by the subject. This article describes how the cognitive strategy can be determined from the subject's ROC curve. The hidden assumptions made when using ROC curves and how these assumptions can be tested are also given. This information is essential to researchers in sensory evaluation as well as those using these methods in a practical setting. [source]