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Volker Schmidtke

Publications and source records attributed to Volker Schmidtke.

4 recordsLinked to original sources
PubMed2003

Assembling a task space: global determination of local shift costs.

Most theorizing on the origin of the costs that are associated with task shifts focuses on local transitions between individual trials. In the present article we argue that this emphasis has resulted in a neglect of more global representational structures, which also determinate shift costs. To substantiate this claim, we employed a set of four tasks that results from a factorial combination of two types of judgment and two judgment-to-response mappings. From previous work it is known that this kind of task combination is associated with a characteristic profile of shift costs as a function of the relation between successive tasks. Previously we have interpreted this profile as an indication of a hierarchically ordered dimensional representation of the two types of judgment and the two judgment-to-response mappings. Such a representation can only be expected to emerge when the two task features, judgment and mapping, vary independently of each other within the same situation. It is shown that the characteristic shift cost profile can indeed only be observed when the performance of any of the four tasks is required in a block of trials. In contrast, with only two tasks occurring in each block of trials, shift costs do not reflect the relation between successive tasks. This finding confirms the importance of global representational structures as a determinant of shift costs beyond local transitions between individual trials.

Adolescent↗
PubMed2002

Processes of task-set reconfiguration: switching operations and implementation operations.

When participants are asked to shift between four dimensionally organized tasks which differ in the type of judgment (numerical vs. spatial) and/or the judgment-to-response mapping (compatible vs. incompatible), a characteristic profile of shift costs can be observed. It can be accounted for in terms of two different types of operations: generalizing switching operations on a dimensionally organized set of task representations and implementation operations [T. Kleinsorge, H. Heuer, Psycholog. Res. 62 (1999) 300]. In a first experiment we corroborated our previous findings by way of a new procedure that makes it possible to estimate shift costs unconfounded by a number of factors that are likely to affect estimates of shift costs based on more conventional procedures. In a second experiment we investigated the endogenous and exogenous nature of the postulated types of operations. The characteristic profile of shift costs disappeared when long precue intervals (PCIs) were used. Augmented by a formal analysis, this finding suggests that both switching and implementation operations are endogenously controlled. In addition, there remained some residual shift costs which were essentially insensitive to the nature of the task shift but depended on the difficulty of the new task. Most likely they reflect a process of consolidation of an already configured task set.

Adolescent↗
PubMed2000

[On the effects of psychoanalytic oriented psychotherapy - an inpatient multicenter study]

Whereas the efficacy of inpatient treatment in socalled psychosomatic rehabilitation clinics in Germany has been well researched and documented, studies involving large samples on the efficacy of inpatient treatment in acute hospitals are lacking. A multicentered retrospective study involving clinics for psychotherapy at three separate universities was conducted on a sample of n=495. The patients were treated on an inpatient basis between April 1990 and July 1998 in one of the clinics. The predominant approach to treatment of these clinics was psychodynamic. Other approaches such as behavioral therapy are integrated. In addition to sociodemographic variables clinical data (SCL-90-R, IIP, BSS, ICD-Diagnosis) at admission and discharge were collected. A follow-up study was not conducted. With an average effect size of 0.84 in terms of clinical scales the results demonstrate good efficacy of inpatient treatment. Effect sizes were high on the depression, obsessive-compulsive and anxiety scale of the SCL-90-R, and were low on the phobia subscale. By self report 55% of all patients indicated they had markedly improved, 22% indicated no change and 6% stated they were worse. 17% of all patients were below the chosen cut-off point of the GSI. Patients with a low level of education took benefit as well from the offered therapy. There was no clear relationship between effect size and length of hospital stay. This may be due to the particular setting of a university clinic.

Journal Article↗