Test-retest reliability, internal consistency, and construct validity of the Farsi version of the Oxford Happiness Inventory

This study examined the reliability and preliminary evidence for validity of a Farsi (Persian) version of the Oxford Happiness Inventory with 309 undergraduate students (161 women and 148 men). Participants completed the Farsi versions of four subscales of the Oxford Happiness Inventory, the Satisfaction with Life Scale, the Beck Depression Inventory, and the Depression-Happiness Scale. Analyses indicated that the Farsi version of the Oxford Happiness Scale has reliability as a measure of well-being and provided some preliminary evidence of construct validity.     

Memory and metamemory for semantic information in obsessive-compulsive disorder

Several studies have been conducted on OCD patients' memory and metamemory performance in episodic tasks. However, there is a clear lack of research addressing these issues for semantic memory (i.e., retrieval of information from long-term memory). Although findings regarding a memory deficit is somewhat equivocal, the empirical evidence clearly demonstrates that OCD patients with primarily checking compulsions show reduced confidence in their memory performance. The purpose of the present study was to investigate memory and metamemory performance of checkers in semantic memory domain. We compared checker OCD patients, non-checker OCD patients and normal controls on their ability to retrieve answers to general knowledge questions with a recall as well as a recognition test. We also investigated prospective (feeling-of-knowing (FOK)) and retrospective (confidence) metamemory judgments. Checker OCs were not poorer in retrieving semantic information from long-term memory. Neither were they less confident about their ability to remember currently unrecallable information in the future (FOK judgments) or about the accuracy of retrieved information (confidence judgments). Moreover, accuracy of metamemory judgments were comparable across groups. Overall, our results revealed that checker OCs do not show a memory or metamemory deficit when semantic memory was concerned, suggesting that any memory and metamemory deficit may be special to recently experienced materials.     

Nonparametric item response theory axioms and properties under nonlinearity and their exemplification with knowledge space theory

This paper investigates the dichotomous Mokken nonparametric item response theory (IRT) axioms and properties under incomparabilities among latent trait values and items. Generalized equivalents of the unidimensional nonparametric IRT axioms and properties are formulated for nonlinear (quasi-ordered) person and indicator spaces. It is shown that monotone likelihood ratio (MLR) for the total score variable and nonlinear latent trait implies stochastic ordering (SO) of the total score variable, but may fail to imply SO of the nonlinear latent trait. The reason for this and conditions under which the implication holds are specified, based on a new, simpler proof of the fact that in the unidimensional case MLR implies SO. The approach is applied in knowledge space theory (KST), a combinatorial test theory. This leads to a (tentative) Mokken-type nonparametric axiomatization in the currently parametric theory of knowledge spaces. The nonparametric axiomatization is compared with the assumptions of the parametric basic local independence model which is fundamental in KST. It is concluded that this paper may provide a first step toward a basis for a possible fusion of the two split directions of psychological test theories IRT and KST.     

Reading and spontaneous speaking fundamental frequency of young Arabic men for Arabic and English languages: a comparative study

Speaking fundamental frequency (SFF), the average fundamental frequency (lowest frequency of a complex periodic sound) measured over the speaking time of a vocal or speech task, is a basic acoustic measure in clinical evaluation and treatment of voice disorders. Currently, there are few data on acoustic characteristics of different sociolinguistic groups, and no published data on the fundamental frequency characteristics of Arabic speech. The purpose of this study was to obtain preliminary data on the SFF characteristics of a group of normal speaking, young Arabic men. 15 native Arabic men (M age = 23.5 yr., SD=2.5) as participants received identical experimental treatment. Four speech samples were collected from each one, Arabic reading, Arabic spontaneous speech, English reading, and English spontaneous speech. Speaking samples, analyzed using the Computerized Speech Lab, showed no significant difference for mean SFF between language and type of speech and none for mean SFF between languages. A significant difference in the mean SFF was found between the types of speech. The SFF used during reading was significantly higher than that for spontaneous speech. Also Arabic men had higher SFF values than those previously reported for young men in other linguistic groups. SFF then might differ among linguistic, dialectical, and social groups and such data may provide clinicians information useful in evaluation and management of voice.     

Acute exposure to a 50 Hz magnetic field impairs consolidation of spatial memory in rats

This study was planned to evaluate the effect of an exposure to magnetic fields on consolidation and retrieval of hippocampus dependent spatial memory using a water maze. In Experiments 1 and 2, rats were trained in a hidden version (spatial) of water maze task with two blocks of four trials. The retention of spatial memory was evaluated 48 h later. Exposure to a 50 Hz 8 mT, but not 2 mT magnetic fields for 20 min immediately after training impaired retention performance. The same time exposure shortly before retention testing had no effect. In Experiment 3, rats were trained in a cued version of water maze with two blocks of four trials. Exposure to magnetic field at 8 mT for 20 min immediately after training did not impair retention performance. These findings indicate that acute exposure to a 50 Hz magnetic field at 8 mT for short time can impair consolidation of spatial memory.     

Memory and consciousness: trace distinctiveness in memory retrievals

The aim of this article was to provide experimental evidence that classical dissociation between levels of consciousness associated with memory retrieval (i.e., implicit or explicit) can be explained in terms of task dependency and distinctiveness of traces. In our study phase, we manipulated the level of isolation (partial vs. global) of the memory trace by means of an isolation paradigm (isolated words among non-isolated words). We then tested these two types of isolation in a series of tasks of increasing complexity: a lexical decision task, a recognition task, and a free recall task. The main result of this study was that distinctiveness effects were observed as a function of the type of isolation (level of isolation) and the nature of the task. We concluded that trace distinctiveness improves subsequent access to the trace, while the level of trace distinctiveness also appears to determine the possibility of conscious or explicit retrieval.