Mueller-Lyer illusion and size estimation performance in schizophrenics compared to normal controls

A size estimation (SE) paradigm and the Mueller-Lyer (ML) illusion were used to examine perceptual disturbances in schizophrenics. 35 reliably diagnosed (DSM III-R) schizophrenics were compared to 20 subjects with no history of psychiatric illness. Perceptual distortions found in previous studies of schizophrenics were only to a certain extent confirmed in the present results. More overestimators were found among the schizophrenics than among the normals on the SE task. The schizophrenics, first of all the chronic patients, also proved to be more prone to the Mueller-Lyer illusion. A reason why the very clear differences between schizophrenics and normals found in previous examinations were not confirmed in the present study, might be that a reliable diagnostic instrument was for the first time used in this kind of study.     

Noradrenaline loss and the disruption of between-CS stimulus generalisation effects in aversion learning

In stimulus blocking the previous conditioning to one stimulus, A, followed by conditioning to the compound stimulus, AB, results in less conditioning to the other stimulus, B. Three experiments were performed to study the effect of the prior pairing of a stimulus A (noisy bottle) with lithium chloride followed by stimulus AB (saccharin plus noisy bottle) and lithium chloride pairings upon the strength of the aversion to the target stimuls B (saccharin) in NA-depleted and control rats. The results obtained were not in keeping with a "blocking" explanation since enhancement, rather than blocking, of the saccharin aversion was obtained, and confirm several recent demonstrations of the "anti-blocking" effect from investigations using the conditioned suppression procedure. DSP4 treatment attenuated the aversion-enhancement ("anti-blocking") effects in all three experiments. The possibility that DSP4-induced noradrenaline depletions may cause some disruption of between-CS associations leading to a lesser higher order conditioning or stimulus generalisation is discussed and the present findings do add further evidence to the conclusion that noradrenaline is intimately involved in attentional processes.     

Visual speech processing: Word-decoding and word-discrimination related to sentence-based speechreading and hearing-impairment

Two aspects of visual speech processing in speechreading (word decoding and word discrimination) were tested in a group of 24 normal hearing and a group of 20 hearing-impaired subjects. Word decoding and word discrimination performance were independent of factors related to the impairment, both in a quantitative and a qualitative sense. Decoding skill, but not discrimination skill, was associated with sentence-based speechreading. The results were interpreted such that, in order to represent a critical component process in sentence-based speechreading, the visual speech perception task must entail lexically induced processing as a task-demand. The theoretical status of the word decoding task as one operationalization of a speech decoding module was discussed (Fodor, 1983). An error analysis of performance in the word decoding/discrimination tasks suggested that the perception of heard stimuli, as well as the perception of lipped stimuli, were critically dependent on the same features; that is, the temporally initial phonetic segment of the word (cf. Marslen-Wilson, 1987). Implications for a theory of visual speech perception were discussed.     

NARROW HEDONISM

Narrow hedonism is defined and defended, as a view according to which pleasurable states are individuated as concrete and total experiential situations of a sentient being at a time. Typical of such situations is that, when we are in them, we are at a certain hedonic level. They feel in a certain way for the creature in them. On this understanding of narrow hedonism, which is the only one making good sense of the theory and which was probably also intended by classical hedonists such as Bentham and Edgeworth, standard objections to hedonism, based on the claim that different pleasures have nothing in common, can be set to one side as misplaced and irrelevant. It is also hard to see how this kind of hedonism can be refined, or revised, in the direction indicated by J.S. Mill, when he wants to distinguish “higher” pleasures from “lower” ones. On this understanding of hedonism, we must claim that, those who want to follow Mill will have to rely on non-hedonistic intuitions and thus desert the hedonist camp altogether.     

Is there an optimal factor structure of the Positive and Negative Syndrome Scale in patients with first‐episode psychosis?

The Positive and Negative Syndrome Scale (PANSS) is the most widely used scale to assess a variety of symptoms in patients with schizophrenia and other psychoses. The factor structure of the PANSS has been examined with confirmatory factor analyses in several studies, but not in a well‐defined first‐episode psychosis sample. The aim of this paper is to examine the statistical fit of five different PANSS models in a first‐episode, non‐affective psychosis sample. Confirmatory factor analyses were performed on PANSS data (n = 588). A main criterion for best fit was defined as the Expected Cross Validation Index (ECVI). No tested model revealed an optimally satisfactory model fit index. The Wallwork/Fortgang five‐factor model demonstrated the most optimal psychometric properties. The corresponding subscales of all evaluated five‐factor models were strongly intercorrelated. The Wallwork/Fortgang five‐factor model was found to be statistically and clinically ideal among patients with first‐episode psychosis. Therefore, we recommend this model in forthcoming studies among patients with first‐episode psychosis. However, to prevent the loss of clinically valuable information on an item level, we do not recommend removing any items from the original form. Our study also implies that the specific choice of model will not have a substantial effect on outcome results in studies on the course and outcome in first‐episode psychosis.     

Gender differences on the Five to Fifteen questionnaire in a non‐referred sample with inattention and hyperactivity‐impulsivity and a clinic‐referred sample with hyperkinetic disorder

Lambek, R., Trillingsgaard, A., Kadesjö, B., Damm, D. & Thomsen, P. H. (2010). Gender differences on the Five to Fifteen questionnaire in a non‐referred sample with inattention and hyperactivity‐impulsivity and a clinic‐referred sample with hyperkinetic disorder. Scandinavian Journal of Psychology 51, 540–447. The aim of the present study was to examine gender differences in children with inattention, hyperactivity, and impulsivity on the Five to Fifteen (FTF) parent questionnaire. First, non‐referred girls (n = 43) and boys (n = 51) with problems of attention and hyperactivity‐impulsivity and then clinic‐referred girls (n = 35) and boys (n = 66) with hyperkinetic disorder (HKD) were compared on the FTF. Results suggested that non‐referred boys were more hyperactive‐impulsive than non‐referred girls, whereas clinic‐referred boys and girl with HKD were more similar than dissimilar on the FTF questionnaire. Secondly, it was examined whether the application of gender mixed norms versus gender specific norms would result in varying proportions of clinic‐referred children with HKD being identified as impaired on the subdomains of the FTF questionnaire. Based on results it was concluded that the use of a gender mixed normative sample may lead to overestimation of impairment in boys with HKD, but the type of sample applied to define impairment on the FTF should depend on the purpose for applying the questionnaire.     

Effect of low dose ionizing radiation exposure in utero on cognitive function in adolescence

Heiervang, K. S., Mednick, S., Sundet, K. & Rund, B. R. (2010). Effect of low dose ionizing radiation exposure in utero on cognitive function in adolescence. Scandinavian Journal of Psychology, 51, 210–215. Radiation from the Chernobyl nuclear power plant meltdown greatly affected several Norwegian counties. The cognitive consequences of in utero exposure to radiation from the Chernobyl accident have been intensely debated. This study examines the cognitive outcomes for those Norwegians who were exposed as fetuses to the fallout from Chernobyl. The participants, 84 adolescents who were exposed in utero to radiation from the most contaminated areas in Norway and 94 adolescents from areas not contaminated by the radiation, were tested on verbal and nonverbal IQ. Two data analyses were conducted. First, using a control‐group design, the IQ scores of exposed and unexposed adolescents were compared. Second, in a timing‐of‐exposure design, those exposed during the most sensitive period were contrasted with those exposed later in gestation. Adolescents exposed to low‐dose ionizing radiation in utero scored significantly lower in full‐scale IQ than unexposed adolescents. The difference was restricted to verbal IQ and was not evident for nonverbal IQ. The effect was not observed in exposed adolescents who had passed the most sensitive gestational period prior to the accident and thus were exposed to the radiation from Chernobyl exclusively after gestational week 16. These participants performed as well as the controls. Although the results should be interpreted cautiously due to the study’s nonrandomized design, the data add new and important support to the hypothesis that the Chernobyl accident may have had a subtle effect on the cognitive functioning of those exposed to low‐dose ionizing radiation in utero during the most sensitive gestational period.     

FAKING IN PERSONNEL SELECTION: TRADEOFFS IN PERFORMANCE VERSUS FAIRNESS RESULTING FROM TWO CUT-SCORE STRATEGIES

Most faking research has examined the use of personality measures when using top-down selection. We used simulation to examine the use of personality measures in selection systems using cut scores and outlined a number of issues unique to these situations. In particular, we compared the use of 2 methods of setting cut scores on personality measures: applicant-data-derived (ADD) and nonapplicant-data-derived (NADD) cut-score strategies. We demonstrated that the ADD strategy maximized mean performance resulting from the selection system in the face of applicant faking but that this strategy also resulted in the displacement of deserving applicants by fakers (which has fairness implications). On the other hand, the NADD strategy minimized displacement of deserving applicants but at the cost of some mean performance. Therefore, the use of the ADD versus NADD strategies can be viewed as a strategic decision to be made by the organization, as there is a tradeoff between the 2 strategies in effects on performance versus fairness to applicants. We quantitatively outlined these tradeoffs at various selection ratios, levels of validity, and amounts of faking in the applicant pool.     

Visual discrimination of vowel duration

Discrimination of vowel duration was explored with regard to discrimination threshold, error bias, and effects of modality and consonant context. A total of 122 normal-hearing participants were presented with disyllabic-like items such as /lal-lal/ or /mam-mam/ in which the lengths of the vowels were systematically varied and were asked to judge whether the first or second vowel was longer. Presentation was either visual, auditory, or audiovisual. Vowel duration differences varied in 24 steps: 12 with a longer first /a/ and 12 with a longer last /a/ (range: ±33–400 ms). Results: 50% JNDs were smaller than the lowest tested step size (33 ms); 75% JNDs were in the 33–66 ms range for all conditions but V /lal/, with a 75% JND at 66–100 ms. Errors were greatest for visual presentation and for /lal-lal/ tokens. There was an error bias towards reporting the first vowel as longer, and this was strongest for /mam-mam/ and when both vowels were short, possibly reflecting a sublinguistic processing strategy.