Inhibited prime-trial distractor responses solely produce the visual spatial negative priming effect

Responding to a target??s current (probe trial) location is slower when it appears at a former distractor-occupied position (i.e., ignored-repetition [IR] trial), relative to when it arises at a new location (i.e., control trial). This RT(IR) > RT(Control) inequality defines the spatial negative priming (SNP) effect in latency terms. It is uncertain whether the elevated RT(IR) is due to the inhibition of the distractor-occupied location or to the inhibition of this location??s assigned manual response (SNP locus issue). The main aim here was to examine the SNP locus issue. Notably, our SNP design used centrally presented visual events and included having two locations share a common response (many:1 location-to-response mapping) and the use of informative (70?% validity) or uninformative probe-trial response cues. The many:1 mapping trials allowed for the detection of location and response inhibition presence. Results showed that the latter, but not the former, causes inhibitory aftereffects (e.g., SNP) following uninformative response cues. Consistent with this finding, when the informative response cue was valid and was assigned to the many:1 probe response that had just served as the prime distractor response, inhibitory aftereffects were eliminated, when the probe target appeared at the prime distractor position (IR trial) or at a new location (distractor?Cresponse repeat trial). Blocked retrieval of stored distractor-processing representations was proposed as the mechanism for inhibitory aftereffect prevention.     

Conditioned fear is modulated by D2 receptor pathway connecting the ventral tegmental area and basolateral amygdala

Excitation of the mesocorticolimbic pathway, originating from dopaminergic neurons in the ventral tegmental area (VTA), may be important for the development of exaggerated fear responding. Among the forebrain regions innervated by this pathway, the amygdala is an essential component of the neural circuitry of conditioned fear. The functional role of the dopaminergic pathway connecting the VTA to the basolateral amygdala (BLA) in fear and anxiety has received little attention. In vivo microdialysis was performed to measure dopamine levels in the BLA of Wistar rats that received the dopamine D(2) agonist quinpirole (1 μg/0.2 μl) into the VTA and were subjected to a fear conditioning test using a light as the conditioned stimulus (CS). The effects of intra-BLA injections of the D(1) antagonist SCH 23390 (1 and 2 μg/0.2 μl) and D(2) antagonist sulpiride (1 and 2 μg/0.2 μl) on fear-potentiated startle (FPS) to a light-CS were also assessed. Locomotor performance was evaluated by use of open-field and rotarod tests. Freezing and increased dopamine levels in the BLA in response to the CS were both inhibited by intra-VTA quinpirole. Whereas intra-BLA SCH 23390 did not affect FPS, intra-BLA sulpiride (2 μg) inhibited FPS. Sulpiride's ability to decrease FPS cannot be attributed to nonspecific effects because this drug did not affect motor performance. These findings indicate that the dopamine D(2) receptor pathway connecting the ventral tegmental area and the basolateral amygdala modulates fear and anxiety and may be a novel pharmacological target for the treatment of anxiety.     

Reviews of current books

Pastoral Psychology -     

Contrasts and correlations in effect-size estimation

This article describes procedures for presenting standardized measures of effect size when contrasts are used to ask focused questions of data. The simplest contrasts consist of comparisons of two samples (e.g., based on the independent t statistic). Useful effect-size indices in this situation are members of the g family (e.g., Hedges's g and Cohen's d ) and the Pearson r . We review expressions for calculating these measures and for transforming them back and forth, and describe how to adjust formulas for obtaining g or d from t , or r from g , when the sample sizes are unequal. The real-life implications of d or g calculated from t become problematic when there are more than two groups, but the correlational approach is adaptable and interpretable, although more complex than in the case of two groups. We describe a family of four conceptually related correlation indices: the alerting correlation, the contrast correlation, the effect-size correlation, and the BESD (binomial effect-size display) correlation. These last three correlations are identical in the simple setting of only two groups, but differ when there are more than two groups.     

The interplay of memory and judgment processes in effects of aging on hindsight bias

Hindsight bias is the phenomenon that after people are presented with the correct answer to a question, their judgment regarding their own past answer to this question is biased toward the correct answer. In three experiments, younger and older adults gave numerical responses to general-knowledge questions and later attempted to recall their responses. For some questions, the correct answer was provided during recall (Experiment 1) or before recall (Experiments 2 and 3). Multinomial model-based analyses show age differences in both recollection bias and reconstruction bias when the correct judgment was in working memory during the recall phase. The authors discuss implications for theories of cognitive aging and theories of hindsight bias.     

On the origins of the task mixing cost in the cuing task-switching paradigm

Poorer performance in conditions involving task repetition within blocks of mixed tasks relative to task repetition within blocks of single task is called mixing cost (MC). In 2 experiments exploring 2 hypotheses regarding the origins of MC, participants either switched between cued shape and color tasks, or they performed them as single tasks. Experiment 1 supported the hypothesis that mixed-tasks trials require the resolution of task ambiguity by showing that MC existed only with ambiguous stimuli that afforded both tasks and not with unambiguous stimuli affording only 1 task. Experiment 2 failed to support the hypothesis that holding multiple task sets in working memory (WM) generates MC by showing that systematic manipulation of the number of stimulus-response rules in WM did not affect MC. The results emphasize the role of competition management between task sets during task control.     

From Environmental Factors to Outcomes: A Test of an Integrated Motivational Sequence

Research based on self-determination theory (SDT; E. L. Deci & R. M. Ryan, 1985, 2000) has shown that motivation is influenced by the social environment and also leads to outcomes. Based on such research, R. J. Vallerand (1997) has posited the existence at different levels of generality of an integrated motivational sequence where environmental factors (e.g., success/failure) influence perceptions of competence, autonomy, and relatedness (psychological mediators), which in turn determine to what extent one exhibits self-determined motivation. Motivation then leads to outcomes. The present study tested the validity of this integrated sequence at the situational level using an experimental design. Participants (N = 359) were randomly assigned to conditions of success or failure on a leisure task and elements of the integrated sequence were assessed. Structural equation modeling analyses provided support for the postulated motivational sequence. Results are discussed in light of SDT.This research was supported by grants and fellowships from the Fonds pour la formation de chercheurs et laide à la recherche (FCAR) and the Social Sciences Humanities Research Council of Canada (SSHRC) to Robert J. Vallerand. We would like to thank Sandrine Passelaigue for her help in collecting the data.     

First-order and second-order spectral 'motion' mechanisms in the human auditory system

Light energy displaced along the retinal photoreceptor array leads to a perception of visual motion. In audition, displacement of mechanical energy along the cochlear hair cell array is conceptually similar but leads to a perception of 'movement' in frequency space (spectral motion)--a rising or falling pitch. In vision there are other types of stimuli that also evoke a percept of motion but do not involve a displacement of energy across the photoreceptors (second-order stimuli). In this study, we used psychophysical methods to determine if such second-order stimuli also exist in audition, and if the resulting percept would rival that of first-order spectral motion. First-order auditory stimuli consisted of a frequency sweep of sixteen non-harmonic tones between 297 and 12123 Hz. Second-order stimuli consisted of the same tones, but with a random subset turned on at the beginning of a trial. During the trial, each tone in sequence randomly changed state (ON-to-OFF, or OFF-to-ON). Thus, state transitions created a 'sweep' having no net energy displacement correlated to the sweep direction. At relatively slow sweep speeds, subjects readily identified the sweep direction for both first-order and second-order stimuli, though accuracy decreased for second-order stimuli as the sweep speed increased. This latter characteristic is also true of some second-order visual stimuli. These results suggest a stronger parallelism between auditory and visual processing than previously appreciated.