Attentional balance and intelligence

Recent studies of neuroimaging during cognitive tasks suggest that most tasks involve the activity of widespread areas in both cerebral hemispheres. In many cases, information must be shared between the two hemispheres. The coordination of these areas involves the brain's attentional networks. Unilateral brain damage often causes asymmetries in attention and reduced speed of processing. Based on these findings it was hypothesized that mental processing in normals will be more efficient when normal people can shift attention to either hemisphere with equal efficiency. Attentional balance was measured by the degree of asymmetry found during the covert visual-orienting task. Intelligence was measured by the Raven Standard Progressive Matrices. Data from two experiments suggest that low asymmetry in attention shifting is associated with higher intelligence.     

Mushroom bodies of the honeybee brain show cell population-specific plasticity in expression of amine-receptor genes

Dopamine and octopamine released in the mushroom bodies of the insect brain play a critical role in the formation of aversive and appetitive memories, respectively. As recent evidence suggests a complex relationship between the effects of these two amines on the output of mushroom body circuits, we compared the expression of dopamine- and octopamine-receptor genes in three major subpopulations of mushroom body intrinsic neurons (Kenyon cells). Using the brain of the honeybee, Apis mellifera, we found that expression of amine-receptor genes differs markedly across Kenyon cell subpopulations. We found, in addition, that levels of expression of these genes change dramatically during the lifetime of the bee and that shifts in expression are cell population-specific. Differential expression of amine-receptor genes in mushroom body neurons and the plasticity that exists at this level are features largely ignored in current models of mushroom body function. However, our results are consistent with the growing body of evidence that short- and long-term olfactory memories form in different regions of the mushroom bodies of the brain and that there is functional compartmentalization of the modulatory inputs to this multifunctional brain center.     

Stimulus Classes Formation in Concurrent Discriminations in Rats as a Function of Overtraining

The Psychological Record - The present two experiments conducted a limited parametric study of the overtraining variable using a whole-partial reversal procedure in rats. Rats received two...     

Mirror reading of words and numbers: Practice and transfer effects

It remains unknown whether mirror reading represents a genuine text processing skill or is based on recognition of visual patterns. The present study attempts to determine whether (1) systematic practice with a particular mirrored typography also improves reading performance for other mirrored typographies, and whether (2) this transfer extends from lexical to numerical material and vice versa. The results show that short-term intensive practice with mirror-reversed words significantly improves reading performance not only for the trained typography but also for other mirrored typographies and mirror-reversed Arabic digits. Practice with mirror-reversed Arabic digits showed a mixed pattern of transfer effects with regard to other digit transformations and there were no transfer effects to lexical material. Hence, for lexical material, at least, improvement after training seems to be based on generalized skill with transfer effects beyond lexical material, rather than on mere improvement of visual recognition of the material used in training.     

Acquired Equivalence of Discriminative Stimuli Following Two Concurrent Discrimination Learning Tasks as a Function of Overtraining in Rats

The Psychological Record - Three experiments examined whether or not the members of each stimulus class between the discriminative stimuli formed during overtraining became functionally equivalent....     

Emergent, untrained stimulus relations in many-to-one matching-to-sample discriminations in rats

The present experiment investigated whether rats formed emergent, untrained stimulus relations in many-to-one matching-to-sample discriminations. In Phase 1, rats were trained to match two samples (triangle and horizontal stripes) to a common comparison (horizontal stripes) and two additional samples (circle or vertical stripes) to another comparison (vertical stripes). Then, in Phase 2, the rats were trained to match the one sample (triangle) to a new comparison (black) and the other sample (circle) to another comparison (white). In the Phase 3 test, half the rats (consistent group) were given two new tasks in which the sample-correct comparison relation was consistent with any emergent stimulus relations that previously may have been learned. The remaining 6 rats (inconsistent group) were given two new tasks in which the sample-correct comparison relation was not consistent with any previously learned emergent stimulus relations. Rats in the consistent group showed more accurate performance at the start of Phase 3, and faster learning to criterion in this phase, as compared with rats in the inconsistent group. This finding suggests that rats may form emergent, untrained stimulus relations between the discriminative stimuli in many-to-one matching-to-sample discriminations.     

Haptic identification of objects and their depictions

Haptic identification of real objects is superior to that of raised two-dimensional (2-D) depictions. Three explanations of real-object superiority were investigated: contribution of material information, contribution of 3-D shape and size, and greater potential for integration across the fingers. In Experiment 1, subjects, while wearing gloves that gently attenuated material information, haptically identified real objects that provided reduced cues to compliance, mass, and part motion. The gloves permitted exploration with free hand movement, a single outstretched finger, or five outstretched fingers. Performance decreased over these three conditions but was superior to identification of pictures of the same objects in all cases, indicating the contribution of 3-D structure and integration across the fingers. Picture performance was also better with five fingers than with one. In Experiment 2, the subjects wore open-fingered gloves, which provided them with material information. Consequently, the effect of type of exploration was substantially reduced but not eliminated. Material compensates somewhat for limited access to object structure but is not the primary basis for haptic object identification.     

The spatial Stroop effect: A comparison of color-word and position-word interference

The Stroop effect is one of the most famous examples of interference in human perception. The present study demonstrates that a position Stroop paradigm, comparable to the classical color-word interference paradigm, resulted in the same pattern of interference for the spatial dimension; however, the interference was significantly weaker. By exchanging the original oral response for a manual response in the spatial paradigm, we showed that the verbal component is crucial for the Stroop effect: Manual responses lead to a disappearance of the interference effect. Moreover, with manual responses word position was recognized at the same speed for the baseline condition and for words that were incongruent as well as congruent with the spatial position. The results indicate (1) that the Stoop effect depends heavily on verbal components and (2) that differing processing speeds between reading and position recognition do not serve as a proper explanation for the effect. In addition, the provided paradigm plausibly transfers the classical color-word interference to the spatial dimension.     

Age,Emotion Regulation,and Affect in Adulthood: The Mediating Role of Cognitive Reappraisal

Evidence indicates that older adults experience high levels of emotional well‐being. However, little is known empirically about the underlying mechanism of this state. The purpose of the present study was to investigate whether emotion regulation mediates the link between age and affect in adulthood. The sample consisted of 516 Japanese participants aged 30 (±1), 50 (±1), and 70 (±1) years, who were registered with an Internet survey company. Cognitive reappraisal and expressive suppression were measured as emotion regulation strategies. Positive and negative affect were assessed. Older participants reported lower negative affect than younger participants, while positive affect was not correlated with age. Cognitive reappraisal partially mediated the relationship between age and affect, whereas expressive suppression did not. The results suggested that age‐related increase in cognitive reappraisal could contribute to improvements in affect, but that another adaptive form of emotion regulation may mediate the relationship between age and affect. Our study thus indicates that developments in emotion regulation could explain the mechanism of stable everyday affect throughout adulthood, and that researchers should further explore another form of adaptive emotion regulation.