No abstract

The rule/plan motor cognition (RPMC) paradigm elicits visually indistinguishable motor outputs, resulting from either plan- or rule-based action-selection, using a combination of essentially interchangeable stimuli. Previous implementations of the RPMC paradigm have used pantomimed movements to compare plan- vs. rule-based action-selection. In the present work we attempt to determine the generalizability of previous RPMC findings to real object interaction by use of a grasp-to-rotate task. In the plan task, participants had to use prospective planning to achieve a comfortable post-handle rotation hand posture. The rule task used implementation intentions (if-then rules) leading to the same comfortable end-state. In Experiment A, we compare RPMC performance of 16 healthy participants in pantomime and real object conditions of the experiment, within-subjects. Higher processing efficiency of rule- vs. plan-based action-selection was supported by diffusion model analysis. Results show a significant response-time increase in the pantomime condition compared to the real object condition and a greater response-time advantage of rule-based vs. plan-based actions in the pantomime compared to the real object condition. In Experiment B, 24 healthy participants performed the real object RPMC task in a task switching vs. a blocked condition. Results indicate that plan-based action-selection leads to longer response-times and less efficient information processing than rule-based action-selection in line with previous RPMC findings derived from the pantomime action-mode. Particularly in the task switching mode, responses were faster in the rule compared to the plan task suggesting a modulating influence of cognitive load. Overall, results suggest an advantage of rule-based action-selection over plan-based action-selection; whereby differential mechanisms appear to be involved depending on the action-mode. We propose that cognitive load is a factor that modulates the advantageous effect of implementation intentions in motor cognition on different levels as illustrated by the varying speed advantages and the variation in diffusion parameters per action-mode or condition, respectively.

Efficient movement selection is crucial in everyday activities. Whether this function is governed by our stress system is so far unknown. In the current study, data from thirty-six young male adults were analyzed. They performed rule- and plan-based movement selection tasks before (session 1) and after (session 2) a psychosocial stressor, or after a control condition without additional social stressor. Results showed that the rule-based efficiency advantage which was observed prior to the psychosocial stressor was significantly reduced afterwards in the whole sample, as well as in the stress group. Regression analyses revealed that this effect was due to a modulation of the plan-based approach. Especially variations—both increase and decrease—in the parasympathetic activity (reflected by the heart rate variability measure RMSSD) appeared to be disadvantageous for plan-based movement selection improvement. In contrast, performance in the rule-based movement selection tasks appeared to be rather invariant to external influences. The current results suggest that autonomic nervous system activity might modulate motor-cognitive performance. This modulatory capability might be selective for plan-based approaches, hence the applied strategy to movement selection could be decisive when it comes to the vulnerability of motor-cognitive processes towards psychosocial stress.

Zusammenfassung: Die aktuellen Anpassungen im Psychologiestudium in Deutschland verändern die Qualifizierungswege von klinisch-neuropsychologisch Interessierten. Auch für potenzielle Nachwuchswissenschaftler_innen sind die Perspektiven über z. B. einen forschungsorientierten Master ohne Approbation noch unklar. Wir skizzieren einige Grenzen und Möglichkeiten angesichts der aktuellen Lage und schlagen eine kombinierte wissenschaftliche und klinisch-neuropsychologische Qualifizierung als Option vor. Dieses Modell könnte eine Brücke zwischen akademischen und patient_innenbezogenen Tätigkeitsfeldern bilden und die Sicherung angewandter Forschung stützen. Um aktuelle wissenschaftliche Standards für den Anwendungsbereich langfristig aufrechtzuerhalten und die neuropsychologische Versorgung zu stärken, müssen der zukünftige wissenschaftliche Nachwuchs und die Flexibilität in dessen Karriereplanung gefördert werden. Eine Limitation ist die noch unbestimmbare Umsetzbarkeit des Modells. Zuständigkeiten müssten geklärt, rechtliche Möglichkeiten evaluiert und ggf. das Modell um weitere Perspektiven ergänzt werden.