Task-set reconfiguration with binary and three-valued task dimensions

 Recently, we [Kleinsorge & Heuer (1999) Psychological Research, 62, 300–312] introduced the notion of generalizing switching operations to account for a characteristic pattern of shift costs that can be observed when participants have to shift between four tasks that result from an orthogonal combination of the two binary task dimensions kind of judgment (numerical vs spatial) and judgment-to-response mapping (compatible vs incompatible). Specifically, while a change of the kind of judgment always results in costs, a change of mapping results in costs only when the kind of judgment is repeated, but results in benefits when the kind of judgment changes as well. In Experiment 1, we replicated and extended this finding with a combination of two spatial kinds of judgment that were more similar to each other and were more unlikely to result in build-in dependencies of the two task dimensions. In Experiment 2, we extended this design to a combination of nine tasks that resulted from a factorial combination of two three-valued task dimensions. In this experiment, shift costs grew monotonically with the number of task dimensions on which a change took place. This outcome is consistent with the assumption that a generalizing switching operation is a forward-acting process that requires a specific target value to switch to. Received: 17 April 2000 / Accepted: 25 August 2000     

The effects of weak perturbations on rapid finger oscillations

Movement control can be position based or amplitude based; in the first case the frame of reference is fixed, while in the second case the origin is at the start of each movement so that in series of movements errors are propagated. In movements aimed at a target the kind of control is task dependent, though the majority of findings suggest a stronger weight of amplitude-based control. In rapid finger oscillations which do not require visuo-motor transformations, control turned out to be position based as revealed by a lack of propagation of small shifts of angular position induced by brief mechanical perturbations; the only effect of the perturbations in addition to the immediate mechanical effect on movement amplitude was enhanced myoelectric activity in both agonists and antagonists which showed up with some delay. The finding of position-based control points to the functional importance of the mechanical characteristics of peripheral musculo-skeletal systems in rapid limb oscillations.     

Differentiating core and co-opted mechanisms in calculation: The neuroimaging of calculation in aphasia

The role of language in exact calculation is the subject of debate. Some behavioral and functional neuroimaging investigations of healthy participants suggest that calculation requires language resources. However, there are also reports of individuals with severe aphasic language impairment who retain calculation ability. One possibility in resolving these discordant findings is that the neural basis of calculation has undergone significant reorganization in aphasic calculators. Using fMRI, we examined brain activations associated with exact addition and subtraction in two patients with severe agrammatic aphasia and retained calculation ability. Behavior and brain activations during two-digit addition and subtraction were compared to those of a group of 11 healthy, age-matched controls. Behavioral results confirmed that both patients retained calculation ability. Imaging findings revealed individual differences in processing, but also a similar activation pattern across patients and controls in bilateral parietal cortices. Patients differed from controls in small areas of increased activation in peri-lesional regions, a shift from left fronto-temporal activation to the contralateral region, and increased activations in bilateral superior parietal regions. Our results suggest that bilateral parietal cortex represents the core of the calculation network and, while healthy controls may recruit language resources to support calculation, these mechanisms are not mandatory in adult cognition.     

Total sleep deprivation increases the costs of shifting between simple cognitive tasks

In two experiments we studied the effects of one night of total sleep deprivation on task-shift costs. In different conditions shifts were between types of judgment (extradimensional shifts) and between stimulus-response mappings (intradimensional shifts). In addition, with an alternating-runs procedure we used short and long response-to-stimulus intervals and also external precues to vary the opportunities for advance configuration of task sets. Under all conditions sleep deprivation increased shift costs derived from the 20% slowest reaction times, which were insensitive to the opportunities for advance configuration. Shift costs derived from the 20% fastest reaction times were increased only for extradimensional shifts. As indicated by congruency effects, the increase of shift costs after a night without sleep cannot be attributed to increased interference between competing task sets. The findings suggest that total sleep deprivation increases task-set instability and thus lapsing, in particular in conditions with long stimulus-to-response intervals and in shift trials. In addition total sleep deprivation seems to increase the duration of an exogenously controlled process involved in extradimensional shifts.     

The effects of brief cognitive-behaviour therapy for pathological skin picking: A randomized comparison to wait-list control

Thirty-four college students suffering from pathological skin picking were randomly assigned to a four-session cognitive-behavioural treatment (n = 17) or a waiting-list condition (n = 17). Severity of skin picking, psycho-social impact of skin picking, strength of skin-picking-related dysfunctional cognitions, and severity of skin injury were measured at pre-, post-, and two-months follow-up assessment. Participants in the treatment condition showed a significantly larger reduction on all measured variables in comparison to the waiting-list condition. The obtained effect sizes for the outcome measures were large, ranging from .90 to 1.89. Treatment effects were maintained at follow-up. In conclusion, cognitive-behavioural therapy, even in brief form, constitutes an adequate treatment option for pathological skin-picking behaviour.     

The Crooked Path from Vagueness to Four-Dimensionalism

Philosophical Studies -     

Kombination von Settings und Verfahren in der Psychotherapie

Literature research and own clinical experiences confirm the significance of a combined use of settings and methods in the area of inpatient and outpatient psychotherapy. For inpatient treatment, the combined use of methods, such as individual psychotherapy, group therapy, creative therapies, and sport, are an essential part of the treatment. In outpatient treatment, the regulations of the German insurance do not permit such combinations. Nevertheless, they occur and are often proactively initiated by the patients. The various combined use of psychotherapy and psychotropics is very well studied, but also the combination of settings, i.e. supplementary inpatient treatment, day treatment, and outpatient treatment have to be considered. While administering their therapies, psychotherapists should keep in mind possibly concurrently ongoing treatments as well as former therapies and their effects on the patients. With the exception of combinations with psychotropic treatment, there exist almost no empirical data in this important field.     

Wrongness and Reasons

Is the wrongness of an action a reason not to perform it? Of course it is, you may answer. That an action is wrong both explains and justifies not doing it. Yet, there are doubts. Thinking that wrongness is a reason is confused, so an argument by Jonathan Dancy. There can’t be such a reason if ‘?-ing is wrong’ is verdictive, and an all things considered judgment about what (not) to do in a certain situation. Such judgments are based on all the relevant reasons for and against ?-ing. If that ?-ing is wrong, while being an all things considered verdict, would itself be a reason, it would upset the balance of reasons: it would be a further reason which has not yet been considered in reaching the verdict. Hence, the judgment wasn’t ‘all things considered' after all. I show that the argument against wrongness being a reason is unsuccessful, because its main assumption is false. Is main assumption is that a consideration which necessarily does not affect the balance of reasons is not a reason. I also argue that there can be no deontic buck-passing account.     

Mind and movement

Voluntary movements embrace both intentional, conscious and post-intentional, largely automatic processes. Here, we examine these types of processes and the relations between them during preparation and execution of voluntary movements. First, a general overview is given about how intentional and post-intentional components are interleaved to enable successful control of purposeful movements. Second, we briefly describe some post-intentional processes that are triggered by preceding intentions. Third, we discuss findings according to which such post-intentional processes or their results can become accessible to conscious awareness. Under such conditions, automatic and conscious processes can co-occur. We show that intentional interventions into post-intentional processes can be overridden by automatic processes, can interfere with automatic processes and can be independent so that their outcomes add to those of automatic processes.