Involuntary retrieval in alphabet-arithmetic tasks: Task-mixing and task-switching costs

This study explores the effects of memory retrieval in task switching. To this end, item-specific stimulus-to-task mappings were manipulated in two alphabet-arithmetic experiments. Letter-stimuli were presented and the responses were verbal letter names. The task was either to name the next letter in the alphabet, (e.g., C D, task plus), or to name the preceding letter (e.g., C B, task minus). The mapping of individual stimuli to the two tasks (and thus to responses) was either consistent (CM) or varied (VM). In Experiment 1, performance was worse for VM items relative to CM items, indicating item-specific task-mapping effects. These task-mapping effects also contributed to mixing costs (i.e., worse performance in mixed-task blocks than in pure-task blocks) but not to switch costs (worse performance in task-switch trials than in repeat trials within mixed blocks). Experiment 2 manipulated pure and mixed tasks between-participants, and the data again showed differential effects of the task-mapping manipulation on mixing costs and switch costs. This suggests that, in these memory-dependent, alphabet-arithmetic tasks, interference due to involuntary task (and/or response) retrieval primarily increases general multi-task effects, such as maintaining activation of the current task.     

Response preparation and code overlap in dual tasks

In a dual-task paradigm, a visual-encoding task with a deferred verbal report of a moving target was combined with a speeded task, in which participants prepared a precued leftward or rightward key-press response that was withheld until an auditory go signal. We manipulated the interval between the response cue and the target for the visual-encoding task, the interval between this target and the go signal, and spatial cross-task compatibility between the direction of the target movement in the visual task and the speeded manual response. The results of two experiments suggest that visual encoding interferes with response preparation and with the initiation of the prepared manual response at a short target-go interval. Also, responses were faster in compatible than in incompatible trials, indicating a cross-task compatibility effect. Experiment 2 reversed this compatibility effect by instruction, suggesting that the compatibility effect is based on response-response overlap. In both experiments, response preparation impaired accuracy in the visual task. Taken together, these results suggest that response processes and visual encoding share common codes and processes.     

Recognizing one’s own clapping: The role of temporal cues

Do individuals recognize their own clapping? We investigated this question with an off-line paradigm in which the perception of the claps is temporally separated from their generation. In a first experiment, we demonstrated that acoustic recordings of clapping provide sufficient information for discriminating between one’s own performance and that of another participant. Self-recognition was still preserved when the claps were reproduced by uniform tones that only retained their temporal pattern. In a subsequent experiment, we verified that the general tempo provides an important cue for self-recognition. Finally, we showed that self-recognition does not rely on concurrent synchronization of actual movements with the auditory sequences. The results are discussed in the light of current theories about perception-action links.     

Orbital prefrontal cortex and guidance of instrumental behavior of rats by visuospatial stimuli predicting reward magnitude

The orbital prefrontal cortex (OPFC) is part of a circuitry mediating the perception of reward and the initiation of adaptive behavioral responses. We investigated whether the OPFC is involved in guidance of the speed of instrumental behavior by visuospatial stimuli predictive of different reward magnitudes. Unoperated rats, sham-lesioned rats, and rats with bilateral lesions of the OPFC by N-methyl-D-aspartate (NMDA) were trained in a visuospatial discrimination task. The task required a lever press on the illuminated lever of two available to obtain a food reward. Different reward magnitudes were permanently assigned to lever presses to respective sides of the operant chamber; that is, responses to one lever (e.g., the left one) were always rewarded with one pellet and responses to the other lever with five pellets. On each trial, the position of the illuminated lever was pseudorandomly determined in advance. Results revealed that OPFC lesions did not impair acquisition of the task, as the speed of conditioned responses was significantly shorter with expectancy of a high reward magnitude. In addition, during reversal, shift and reshift of lever position–reward magnitude contingencies and under extinction conditions, performance of the OPFC-lesioned and control groups did not differ. It is concluded that the OPFC in rats might not be critical for adapting behavioral responses to changes of stimulus–reward magnitude contingencies signaled by visuospatial cues.     

Receiving instrumental support at work: when help is not welcome

Although the role of social support in promoting employees' health and well-being has been studied extensively, the evidence is inconsistent, sometimes even suggesting that social support might have negative effects. The authors examined some psychological processes that might explain such effects. On the basis of the threat-to-self-esteem model, the authors tested the hypothesis that receiving imposed support elicits negative reactions, which are moderated by someone's need for support. The authors distinguished 3 different reactions: (a) self-related, (b) interaction-related, and (c) physiological. The results of an experiment with 48 temporary administrative workers generally confirmed the hypothesis. Imposed support elicited negative reactions, except when there was an unsolvable problem, but even then the effect of imposed support was not positive but neutral.     

Emerging selves: representational foundations of subjectivity

A hypothetical evolutionary scenario is offered meant to account for the emergence of mental selves. According to the scenario, mental selves are constructed to solve a source-attribution problem. They emerge when internally generated mental contents (e.g., thoughts and goals) are treated like messages arising from external personal sources. As a result, mental contents becomes attributed to the self as an internal personal source. According to this view, subjectivity is construed outward-in, that is, one's own mental self is derived from, and is secondary to, the mental selves perceived in others. The social construction of subjectivity and selfhood relies on, and is maintained in, various discourses on subjectivity.     

Internistische Psychosomatik

Zusammenfassung Die psychische Komorbidität internistischer Patienten im Sinne einer ICD-Diagnose des Kapitels F beträgt mehr als 35%: Neurotische, besonders somatoforme, Schmerz-, affektive Störungen und Suchterkrankungen sind häufig. Die Liegedauer ist bei psychischer Komorbidität deutlich erhöht. Es benötigen 5% der internistischen Patienten ein psychosomatisches Konsil. Neue, komplexe Behandlungsstrategien, wie Transplantationen, Kardioverter-Defibrillatoren, Medikamentenpumpen, erfordern häufig spezifische psychosoziale Interventionen. Ältere Patienten haben Erkrankungen, die zunehmend chronifizieren und komplexer werden. Damit werden Lebensqualität und psychische Komorbidität zu zentralen Outcomevariablen der Volkskrankheiten. Das zweite große Aufgabenfeld internistischer Psychosomatik ist die Untersuchung und die Behandlung psychosomatischer Patienten im engeren Sinne (Essstörungen, Schmerz- und somatoforme Störungen), weil internistische Diagnostik und Therapie erforderlich oder die Motivation der Patienten primär somatisch ist. Organisationsmodelle reichen von Konsil-/Liaisondiensten bis zu integrierten psychosomatischen Abteilungen oder Fachabteilungen an Allgemeinkrankenhäusern. Aussichtsreiche Forschungsstrategien werden neben der Erforschung psychosomatischer Mechanismen in der Entwicklung pragmatischer Behandlungsprogramme, ihrer Überprüfung in klinischen Studien und der Versorgungsforschung gesehen. Darüber hinaus sollte eine Intensivierung nationaler und internationaler Forschungsnetze erfolgen, wenn immer möglich unter Beteiligung anderer Disziplinen, um auch im Bereich der Forschung konkurrenzfähig zu bleiben.Herrn Prof. Dr. Ernst Richard Petzold zum 65. Geburtstag gewidmet.     

Empfehlungen zur Behandlungspraxis bei psychotherapeutischen Kriseninterventionen

Ohne Zusammenfassung     

Sun compass orientation in seed-caching corvids: its role in spatial memory

The role of sun compass orientation in spatial memory of Clark’s nutcrackers, Nucifraga columbiana, and pinyon jays, Gymnorhinus cyanocephalus, was studied in a series of cache recovery experiments. Birds were tested in an octagonal outdoor aviary with sand-filled cups inserted in the floor. For caching, only 12 such cups in a 90° sector were available, while for recovery 4–7 days later all 48 cups in the entire aviary were open. In control tests, the birds concentrated their search activity in the sector where they had cached. When their internal clock was shifted 6 h between caching and recovery, pinyon jays shifted their search activity to the 90° adjacent sector, as predicted if the sun compass was used. Clark’s nutcrackers did not respond to the first clock-shift; however, they, too, shifted their search activity after a second clock-shift back to normal. This suggests that the sun compass is a component of spatial memory in both species. Clark’s nutcrackers, however, seem to rely on their sun compass to a lesser degree than pinyon jays or the previously studied scrub jays. A comparison of the findings indicates that the role of the sun in spatial memory might reflect differences in habitat and ecology of the three corvid species. Received: 18 February 1999 / Accepted after revision: 17 September 1999