The visual orientation memory of Drosophila requires Foraging (PKG) upstream of Ignorant (RSK2) in ring neurons of the central complex

Orientation and navigation in a complex environment requires path planning and recall to exert goal-driven behavior. Walking Drosophila flies possess a visual orientation memory for attractive targets which is localized in the central complex of the adult brain. Here we show that this type of working memory requires the cGMP-dependent protein kinase encoded by the foraging gene in just one type of ellipsoid-body ring neurons. Moreover, genetic and epistatic interaction studies provide evidence that Foraging functions upstream of the Ignorant Ribosomal-S6 Kinase 2, thus revealing a novel neuronal signaling pathway necessary for this type of memory in Drosophila.     

The locus of tool-transformation costs

Transformations of hand movements by tools such as levers or electronic input devices can invoke performance costs compared to untransformed movements. This study investigated by means of the Psychological Refractory Period (PRP) paradigm at which stage of information processing such tool-transformation costs arise. We used an inversion transformation, that is, the movement of the operating hand was transformed into a spatially incompatible movement of a lever. As a basic tool-transformation effect, the initiation of inverted tool movements was delayed compared to noninverted movements. Experiment 1 suggested a central (or postcentral) locus of this tool-transformation effect and ruled out a (precentral) perceptual locus. Experiments 2 and 3 confirmed the central locus and ruled out a later, motor-related stage of processing. The results show that spatially incompatible tool movements delay a capacity-limited stage of information processing, often referred to as response selection.     

The role of cue-response mapping in motorvisual impairment and facilitation: evidence for different roles of action planning and action control in motorvisual dual-task priming

Previous research has shown that actions impair the visual perception of categorically action-consistent stimuli. On the other hand, actions can also facilitate the perception of spatially action-consistent stimuli. We suggest that motorvisual impairment is due to action planning processes, while motorvisual facilitation is due to action control mechanisms. This implies that because action planning is sensitive to modulations by cue-response mapping so should motorvisual impairment, while motorvisual facilitation should be insensitive to manipulations of cue-response mapping as is action control. We tested this prediction in three dual-task experiments. The impact of performing left and right key presses on the perception of unrelated, categorically or spatially consistent, stimuli was studied. As expected, we found motorvisual impairment for categorically consistent stimuli and motorvisual facilitation for spatially consistent stimuli. In all experiments, we compared congruent with incongruent cue-key mappings. Mapping manipulations affected motorvisual impairment, but not motorvisual facilitation. The results support our suggestion that motorvisual impairment is due to action planning, and motorvisual facilitation to action control.     

Digital embryos: a novel technical approach to investigate perceptual categorization in pigeons (Columba livia) using machine learning

Animal Cognition - Pigeons are classic model animals to study perceptual category learning. To achieve a deeper understanding of the cognitive mechanisms of categorization, a careful consideration...     

Perceiving by proxy: Effect-based action control with unperceivable effects

Anticipations of future sensory events have the potential of priming motor actions that would typically cause these events. Such effect anticipations are generally assumed to rely on previous physical experiences of the contingency of own actions and their ensuing effects. Here we propose that merely imagined action effects may influence behaviour similarly as physically experienced action effects do. Three experiments in the response–effect compatibility paradigm show that the mere knowledge of action–effect contingencies is indeed sufficient to incorporate these effects into action control even if the effects are never experienced as causally linked to own actions. The experiments further highlight constraints for this mechanism which seems to be rather effortful and to depend on explicit intentions.     

Diagnostic Work through Evidence-Based Guidelines: Avoiding Gaps Between Development and Implementation of a Guideline for Problem Behaviour in Elderly Care

Diagnostic work is the reflexive work of figuring out what issues are at stake and determining the scope for action. This work is not generally accommodated by evidence-based guidelines, which generally promote a uniform, predefined approach to solving healthcare problems that risk narrowing the opportunities for diagnostic work in healthcare practice. Consequently, guidelines are often criticised as too general to solve situated, individual healthcare problems and gaps between guidelines and their implementation are often reported. The Netherlands has developed a guideline for problem behaviour in elderly care, explicitly designed for diagnostic work, thus stimulating a situated approach. Relational problem behaviour is highly embedded in its context. The guideline stimulates diagnostic work, which helps to unravel problem behaviour and is opening alternatives in elderly care. Diagnostic work does not transfer guideline development problems to healthcare practice, but simply structures the decision-making process without giving a predefined answer. Diagnostic work is thus important to consider in order to avoid a gap between guideline development and implementation.     

Zum Stand der forensischen und forensisch-psychiatrischen Nachsorge in der Bundesrepublik Deutschland (Daten aus der sog. Pfingstabfrage 2013)

In 2007 forensic aftercare was integrated into the German Penal Code as part of legal supervision. Since then a large and growing number of patients have been supervised by forensic psychiatric aftercare units throughout Germany. Due to the federal system in Germany the system of forensic aftercare has developed differently in the 16 federal states. The number of patients looked after varies widely and the implementation of several legal norms also differs from state to state. This article gives an overview of the situation of forensic aftercare in the different German federal states and presents some specific characteristics of the development.     

Is the superior verbal memory span of Mandarin speakers due to faster rehearsal?

It is well established that digit span in native Chinese speakers is atypically high. This is commonly attributed to a capacity for more rapid subvocal rehearsal for that group. We explored this hypothesis by testing a group of English-speaking native Mandarin speakers on digit span and word span in both Mandarin and English, together with a measure of speed of articulation for each. When compared to the performance of native English speakers, the Mandarin group proved to be superior on both digit and word spans while predictably having lower spans in English. This suggests that the Mandarin advantage is not limited to digits. Speed of rehearsal correlated with span performance across materials. However, this correlation was more pronounced for English speakers than for any of the Chinese measures. Further analysis suggested that speed of rehearsal did not provide an adequate account of differences between Mandarin and English spans or for the advantage of digits over words. Possible alternative explanations are discussed.     

The Rhythm Method: A New Method for Measuring Cognitive Load—An Experimental Dual‐Task Study

The present study joins a series of studies that used the dual‐task paradigm to measure cognitive load while learning with multimedia instruction. The goal of the current work was to develop a secondary task, to measure cognitive load in a direct and continuous way using intra‐individual, behavioral measures. The new task is achieved by utilizing internalized cues. More specifically, a previously practiced rhythm is executed continuously by foot tapping (secondary task) while learning (primary task). Precision of the executed rhythm was used as indicator for cognitive load—the higher the precision, the lower cognitive load. The suitability of this method was examined by two multimedia experiments (n₁ = 30; n₂ = 50). Cognitive load was manipulated by seductive details (Experiment 1: with vs. without) and modality (Experiment 2: on‐screen text vs. narration). Learners who learned under low cognitive load conditions (Experiment 1: without seductive details; Experiment 2: narration) showed significantly higher rhythm precision. These results provide evidence that rhythm precision allows for a precise and continuous measurement of cognitive load during learning. Copyright © 2014 John Wiley & Sons, Ltd.