Decomposing sources of response slowing in the PRP paradigm

The mechanism underlying the reaction time (RT2) slowing to the 2nd of 2 successively presented stimuli (S1 and S2) in the psychological refractory period paradigm was investigated. Stimulus onset synchrony (SOA) between S1 and S2, contrast of S2, and Task 2 set-level compatibility was manipulated. Specifically, the authors used a psychophysiological approach to examine RT2 slowing in trials in which the reaction time to S1 (RT1) was shorter than the SOA. For trials with RT1 < SOA, the clear decrease in RT2 with increasing SOA was underadditive with the S2 contrast effect, but additive with compatibility. Electrophysiological measures revealed an exclusively premotoric locus of RT2 slowing. These findings indicate that a central bottleneck stage is occupied for some period after response to S1 execution, consistent with an extended response selection bottleneck account.     

Knowledge about suicide and local suicide prevalence: comparison of Estonia and Austria

Knowledge about suicide might be positively correlated with local suicide prevalence. This hypothesis was tested with a sample of 107 medical and social science undergraduates from Estonia, a country with a high suicide rate, using Hubbard and McIntosh's 1992 Revised Facts on Suicide Quiz. Compared (independent-groups t tests) with a sample of undergraduates from Austria, which has a markedly lower suicide rate, Estonians presented significantly higher overall knowledge about suicide (d = 0.39), particularly concerning demographic and epidemiological facts about suicide (d = 0.77) but not pertaining to clinical and interpersonal knowledge contents (d = -0.06). Study limitations and suggestions for extension of this preliminary inquiry are discussed.     

Vierzig Jahre Richtlinien-Psychotherapie in Deutschland

On the 3rd of May 1967, 40 years ago, the Federal Comittee of Physicians and Health Services enacted the guidelines for ?analytic and psychodynamic psychotherapy in the medical care by panel doctors“ (?Psychotherapy Guidelines“). That short text (three and a half DIN A4 pages) was the starting point of a sheer revolutionary development. It became the basis of a health care system, which allows the total financing of relative comprehensive psychotherapeutic treatments in a worldwide unique context.     

Central slowing during the night

The present study determined whether central information processing is subject to a circadian rhythm and, therefore, contributes to the well-known time-of-day effect on reaction time (RT). To assess the duration of central processing chronometrically, we employed the psychological refractory period (PRP) paradigm. In this task, subjects make fast responses to two successive stimuli. RT to the second stimulus is usually prolonged as the interval between the two stimuli decreases. This PRP effect is commonly attributed to a central-processing bottleneck. Subjects performed the PRP task every 2 hr during 28 hr of constant wakefulness under controlled conditions. The PRP effect was most pronounced in the early morning. We conclude that central processing is subject to a circadian rhythm, exhibiting a slowing during the night and a nadir in the early morning.     

Both exposure to a novel context and associative learning induce an upregulation of AKAP150 protein in mouse hippocampus

A-kinase anchoring protein 150 (AKAP150) is a multi-enzyme signaling complex that coordinates the action of PKA, PKC, and PP2B at neuronal membranes and synapses. We measured levels of AKAP150 protein in the hippocampus 6h after training mice in a contextual fear conditioning paradigm. In contextual fear conditioning mice learn to associate a context with a footshock presentation. Mice were divided in four experimental groups with different training protocols: naive, no footshock exposure, immediate footshock exposure, and footshock 3min after exposure to the context. We found that AKAP150 protein levels were increased upon exposing mice to the novel context independent of the training protocol. However, when the animals were habituated to the experimental context, only mice that learned to associate the context with the footshock showed an upregulation of AKAP150. We suggest that upregulated levels of AKAP150 contribute to processing the exposure to a novel context and associative learning.     

Instrument specificity in experienced musicians

Previous studies have shown that experienced pianists have acquired integrated action-effect (A-E) associations. In the present study, we were interested in how specific these associations are for the own instrument by investigating pianists and guitarists. A-E associations were examined by testing whether the perception of a “potential” action-effect has an influence on actions. Participants played chords on their instrument in response to visual stimuli, while they were presented task-irrelevant auditory distractors (congruent or incongruent) in varying instrument timbre. In Experiment 1, pianists exhibited an interference effect with timbres of their own instrument category (keyboard instruments: piano and organ). In Experiment 2 guitarists showed an interference effect only with guitar timbre. Thus, integrated A-E associations primarily seem to consist of a specific component on a sensory-motor level involving the own instrument. Additionally, categorical knowledge about how an instrument is played seems to be involved.     

Knowing when to hear aids what to hear

Temporal preparation often has been assumed to influence motor stages of information processing. Recent studies, however, challenge this notion and provide evidence for a facilitation of visual processing. The present study was designed to investigate whether perceptual processing in the auditory domain also benefits from temporal preparation. To this end, we employed a pitch discrimination task. In Experiment 1, discrimination performance was clearly improved when participants were temporally prepared. This finding was confirmed in Experiment 2, which ruled out possible influences of short-term memory. The results support the notion that temporal preparation enhances perceptual processing not only in the visual, but also in the auditory, modality.     

Security and potential level preferences with thresholds

The security level models of Gilboa [1988. A combination of expected utility and maxmin decision criteria. Journal of Mathematical Psychology, 32, 405-420] and of Jaffray [1988. Choice under risk and the security factor: An axiomatic model. Theory and Decision, 24, 169-200] as well as the security and potential level model of Cohen [1992. Security level, potential level, expected utility: A three-criteria decision model under risk. Theory and Decision, 33, 101-104] and Essid [1997. Choice under risk with certainty and potential effects: A general axiomatic model. Mathematical Social Sciences, 34, 223-247] successfully accommodate classical Allais paradoxes while they offer an interesting explanation for their occurrence. However, experimental data suggest a systematic violation of these models when lotteries with low probabilities of bad or good outcomes are involved. In our opinion, one promising candidate for the explanation of these violations is the assumption of thresholds in the perception of security and potential levels. The present paper develops an axiomatic model that allows for such thresholds, so that the derived representation of preferences can accommodate the observed violations of the original security and potential level models.     

Compound cue processing within the fast and frugal heuristics approach in nonlinearly separable environments

Three experiments investigated whether participants used Take The Best (TTB) Configural, a fast and frugal heuristic that processes configurations of cues when making inferences concerning which of two alternatives has a higher criterion value. Participants were presented with a compound cue that was nonlinearly separable from its elements. The compound was highly valid in Experiments 1 and 2, but invalid in Experiment 3. Participants’ causal mental models were manipulated via instructions: participants were either told that cues acted through the same causal mechanism (configural causal model), through different causal mechanisms (elemental causal model), or the causal mechanisms were not specified (neutral causal model). A high percentage of participants used TTB-Configural when they had a configural causal model and a highly valid compound existed, suggesting that causal knowledge can be incorporated in otherwise very basic cognitive mechanisms to allow fine-grained adaptation to complex task structures.