TY  - JOUR
A1  - Hoffmann, Mareike A.
A1  - Pieczykolan, Aleks
A1  - Koch, Iring
A1  - Huestegge, Lynn
T1  - Two sources of task prioritization: The interplay of effector-based and task order-based capacity allocation in the PRP paradigm
JF  - Attention, Perception, & Psychophysics
N2  - When processing of two tasks overlaps, performance is known to suffer. In the well-established psychological refractory period (PRP) paradigm, tasks are triggered by two stimuli with a short temporal delay (stimulus onset asynchrony; SOA), thereby allowing control of the degree of task overlap. A decrease of the SOA reliably yields longer RTs of the task associated with the second stimulus (Task 2) while performance in the other task (Task 1) remains largely unaffected. This Task 2-specific SOA effect is usually interpreted in terms of central capacity limitations. Particularly, it has been assumed that response selection in Task 2 is delayed due to the allocation of less capacity until this process has been completed in Task 1. Recently, another important factor determining task prioritization has been proposed—namely, the particular effector systems associated with tasks. Here, we study both sources of task prioritization simultaneously by systematically combining three different effector systems (pairwise combinations of oculomotor, vocal, and manual responses) in the PRP paradigm. Specifically, we asked whether task order-based task prioritization (SOA effect) is modulated as a function of Task 2 effector system. The results indicate a modulation of SOA effects when the same (oculomotor) Task 1 is combined with a vocal versus a manual Task 2. This is incompatible with the assumption that SOA effects are solely determined by Task 1 response selection duration. Instead, they support the view that dual-task processing bottlenecks are resolved by establishing a capacity allocation scheme fed by multiple input factors, including attentional weights associated with particular effector systems.
KW  - cognitive and attentional control
KW  - dual-task performance
KW  - dual task procedures (PRP) Introduction In everyday
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-235365
SN  - 1943-3921
VL  - 82
ER  - 
TY  - THES
A1  - Hoffmann, Mareike
T1  - Effector System Prioritization in Multitasking
T1  - Effektorsystempriorisierung im Multitasking
N2  - Multitasking, defined as performing more than one task at a time, typically yields performance decrements, for instance, in processing speed and accuracy. These performance costs are often distributed asymmetrically among the involved tasks. Under suitable conditions, this can be interpreted as a marker for prioritization of one task – the one that suffers less – over the other. One source of such task prioritization is based on the use of different effector systems (e.g., oculomotor system, vocal tract, limbs) and their characteristics. The present work explores such effector system-based task prioritization by examining to which extent associated effector systems determine which task is processed with higher priority in multitasking situations. Thus, three different paradigms are used, namely the simultaneous (stimulus) onset paradigm, the psychological refractory period (PRP) paradigm, and the task switching paradigm. These paradigms invoke situations in which two (in the present studies basic spatial decision) tasks are a) initiated at exactly the same time, b) initiated with a short varying temporal distance (but still temporally overlapping), or c) in which tasks alternate randomly (without temporal overlap). The results allow for three major conclusions: 1. The assumption of effector system-based task prioritization according to an ordinal pattern (oculomotor > pedal > vocal > manual, indicating decreasing prioritization) is supported by the observed data in the simultaneous onset paradigm. This data pattern cannot be explained by a rigid “first come, first served” task scheduling principle. 2. The data from the PRP paradigm confirmed the assumption of vocal-over-manual prioritization and showed that classic PRP effects (as a marker for task order-based prioritization) can be modulated by effector system characteristics. 3. The mere cognitive representation of task sets (that must be held active to switch between them) differing in effector systems without an actual temporal overlap in task processing, however, is not sufficient to elicit the same effector system prioritization phenomena observed for overlapping tasks. In summary, the insights obtained by the present work support the assumptions of parallel central task processing and resource sharing among tasks, as opposed to exclusively serial processing of central processing stages. Moreover, they indicate that effector systems are a crucial factor in multitasking and suggest an integration of corresponding weighting parameters in existing dual-task control frameworks.
N2  - Das gleichzeitige Bearbeiten von mehreren Aufgaben (Multitasking) führt in der Regel zu schlechterer Performanz, zum Beispiel bezüglich Geschwindigkeit und Genauigkeit der Aufgabenausführung. Diese sogenannten Doppelaufgaben- (oder Multitasking-) Kosten sind oft asymmetrisch auf die involvierten Aufgaben verteilt. Dies kann unter bestimmten Gegebenheiten als Priorisierung von jenen Aufgaben, die mit geringeren Kosten assoziiert sind über jene, die stärker durch die Doppelaufgabensituation leiden, interpretiert werden. Eine Quelle für solch eine Aufgabenpriorisierung sind unterschiedliche Effektorsysteme (z.B. Blickbewegungsapparat, Extremitäten, Vokaltrakt), mit denen die Aufgaben jeweils ausgeführt werden sollen. Die vorliegende Arbeit untersucht solche effektorsystembasierte Priorisierung, das heißt, inwiefern assoziierte Effektorsysteme determinieren, ob Aufgaben in Multitasking-Situationen priorisiert verarbeitet werden. Dazu wurden drei verschiedene experimentelle Paradigmen genutzt: a) das „Simultane Stimulus-Darbietungs-Paradigma“, b) das „Psychologische Refraktärperioden-Paradigma“ und c) das „Aufgabenwechsel-Paradigma“. Innerhalb dieser Paradigmen werden Reaktionen (Reaktionszeiten und Fehlerraten) gemessen und zwischen verschiedenen Effektorsystemen verglichen, die a) zum genau gleichen Zeitpunkt gestartet werden, b) mit einem kurzen, variierten zeitlichen Versatz gestartet werden, aber in ihrer Ausführung überlappen, oder c) zwischen denen in unvorhersehbarer Reihenfolge hin und her gewechselt werden soll. Entsprechend dieser drei Ansätze erlauben die Ergebnisse drei wichtige Schlussfolgerungen: 1. Unter simultanem Einsetzen der Aufgabenverarbeitung (und damit ohne extern suggerierte Reihenfolge) folgen Doppelaufgabenkontrollprozesse einem ordinalen Priorisierungsmuster auf Basis der mit den Aufgaben assoziierten Effektorsysteme in der Reihenfolge: okulomotorisch > pedal > vokal > manuell (im Sinne einer absteigenden Priorisierung). Dieses Muster ist nicht durch Bearbeitungsgeschwindigkeit im Sinne eines „wer zuerst kommt, mahlt zuerst“-Prinzips erklärbar. 2. Eine Aufgabenpriorisierung, die auf einer externen Aufgabenreihenfolge basiert (gemessen im PRP-Effekt), kann durch die mit den Aufgaben assoziierten Effektorsysteme moduliert werden. 3. Systematische effektorsystembasierte Aufgabenpriorisierung ist nur dann konsistent zu beobachten, wenn Teile der Aufgabenverarbeitung zeitlich überlappen. Eine rein mentale Repräsentation einer Aufgabe, die in einem anderen Effektorsystem ausgeführt werden soll, reicht nicht dazu aus, um das oben beschriebene Priorisierungsmuster vollständig zu instanziieren. Alles in allem sprechen die Ergebnisse der vorliegenden Arbeit für parallele (und gegen ausschließlich serielle) Reaktionsauswahlprozesse und dafür, dass limitierte kognitive Ressourcen zwischen Aufgaben aufgeteilt werden. Außerdem zeigen die vorliegenden Ergebnisse den substantiellen Einfluss von Effektorsystemen auf Ressourcenzuweisungsprozesse in Mehrfachaufgabensituationen und legen nahe, entsprechende Gewichtungsparameter in bestehende Modelle zu Doppelaufgabenkontrolle zu integrieren.
KW  - Mehrfachtätigkeit
KW  - task prioritization
KW  - response modalities
KW  - cognitive control
KW  - Multitasking
KW  - Effektorsysteme
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-201084
ER  - 
TY  - JOUR
A1  - Hoffmann, Mareike A.
A1  - Koch, Iring
A1  - Huestegge, Lynn
T1  - Are some effector systems harder to switch to? In search of cost asymmetries when switching between manual, vocal, and oculomotor tasks
JF  - Memory & Cognition
N2  - In task-switching studies, performance is typically worse in task-switch trials than in task-repetition trials. These switch costs are often asymmetrical, a phenomenon that has been explained by referring to a dominance of one task over the other. Previous studies also indicated that response modalities associated with two tasks may be considered as integral components for defining a task set. However, a systematic assessment of the role of response modalities in task switching is still lacking: Are some response modalities harder to switch to than others? The present study systematically examined switch costs when combining tasks that differ only with respect to their associated effector systems. In Experiment 1, 16 participants switched (in unpredictable sequence) between oculomotor and vocal tasks. In Experiment 2, 72 participants switched (in pairwise combinations) between oculomotor, vocal, and manual tasks. We observed systematic performance costs when switching between response modalities under otherwise constant task features and could thereby replicate previous observations of response modality switch costs. However, we did not observe any substantial switch-cost asymmetries. As previous studies using temporally overlapping dual-task paradigms found substantial prioritization effects (in terms of asymmetric costs) especially for oculomotor tasks, the present results suggest different underlying processes in sequential task switching than in simultaneous multitasking. While more research is needed to further substantiate a lack of response modality switch-cost asymmetries in a broader range of task switching situations, we suggest that task-set representations related to specific response modalities may exhibit rapid decay.
KW  - cognitive control
KW  - task switching
KW  - response modalities
Y1  - 2022
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-324887
VL  - 50
IS  - 7
ER  -