Matching Items (2)
Description
Sustained attention, the ability to concentrate on a stimulus or task over a prolonged period, is essential for goal pursuit and fulfillment. Sustained attention failures can have catastrophic consequences, underscoring the importance of understanding the mechanisms that underlie variability in sustained attention, and developing interventions targeting these mechanisms to reduce such failures. A growing body of research implicates the brainstem locus coeruleus (LC) as a core modulator of attention and arousal. Activation of LC afferents, such as the trigeminal nerve, may indirectly modulate the LC. The altered LC activity could theoretically be tracked via well-established psychological and physiological indicators of attention and arousal, such as performance, self-reports of attention state, and pupillary activity during attention tasks. The present study tests the hypothesis that continuous transcranial direct current stimulation (tDCS) over the trigeminal nerve of the face improves attentional state, attentional performance, and pupillary reactivity via indirect modulation of the LC. Participants received 2 mA of anodal or cathodal stimulation or sham stimulation over the dorsolateral prefrontal cortex while completing the Psychomotor Vigilance Task. Participants occasionally reported on their attentional state. Pupillary activity was recorded continuously throughout the task. To compare patterns of attention task performance, frequency of task-unrelated thoughts, and pupillary activity across time by stimulation condition, linear mixed-effects models were implemented.
The results replicate the complex interplay between attentional state, attentional performance, and pupillary activity reported in the literature. Specifically, a ubiquitous pattern of performance deterioration was observed, which coincided with an increase in task-unrelated thoughts and reduced pretrial and task-evoked pupil responses. However, tDCS over the face did not produce significant effects compared to the sham condition in attention task performance, proportion of task-unrelated thoughts, and pupillary activity that would indicate LC modulation. This study addresses the causal relations between LC activity, attentional state, attentional performance, and pupillary reactivity that are still poorly understood in human subjects. The findings reported here support the dominant theory of the role of the LC in attentional processes but fail to support hypotheses suggesting that tDCS of the trigeminal nerve influences activity of the LC and indicators of LC activity.
ContributorsTorres, Alexis Stephanie (Author) / Brewer, Gene A (Thesis advisor) / Robison, Matthew K (Committee member) / McClure, Samuel M (Committee member) / Helms Tillery, Stephen (Committee member) / Arizona State University (Publisher)
Created2022
Description
ABSTRACT
Learning a novel motor pattern through imitation of the skilled performance of an expert has been shown to result in better learning outcomes relative to observational or physical practice. The aim of the present project was to examine if the advantages of imitational practice could be further augmented through a supplementary technique derived from my previous research. This research has provided converging behavioral evidence that dyads engaged in joint action in a familiar task requiring spatial and temporal synchrony end up developing an extended overlap in their body representations, termed a joint body schema (JBS). The present research examined if inducing a JBS between a trainer and a novice trainee, prior to having the dyad engage in imitation practice on a novel motor pattern would enhance both of the training process and its outcomes.
Participants either worked with their trainer on a familiar joint task to develop the JBS (Joint condition) or performed a solo equivalent of the task while being watched by their trainer (Solo condition). Participants In both groups then engaged in blocks of alternating imitation practice and free production of a novel manual motor pattern, while their motor output was recorded. Analyses indicated that the Joint participants outperformed the Solo participants in the ability to synchronize the spatial and temporal components of their imitation movements with the trainer’s pattern-modeling movements. The same group showed superior performance when attempting to freely produce the pattern. These results carry significant theoretical and translational potentials for the fields of motor learning and rehabilitation.
Learning a novel motor pattern through imitation of the skilled performance of an expert has been shown to result in better learning outcomes relative to observational or physical practice. The aim of the present project was to examine if the advantages of imitational practice could be further augmented through a supplementary technique derived from my previous research. This research has provided converging behavioral evidence that dyads engaged in joint action in a familiar task requiring spatial and temporal synchrony end up developing an extended overlap in their body representations, termed a joint body schema (JBS). The present research examined if inducing a JBS between a trainer and a novice trainee, prior to having the dyad engage in imitation practice on a novel motor pattern would enhance both of the training process and its outcomes.
Participants either worked with their trainer on a familiar joint task to develop the JBS (Joint condition) or performed a solo equivalent of the task while being watched by their trainer (Solo condition). Participants In both groups then engaged in blocks of alternating imitation practice and free production of a novel manual motor pattern, while their motor output was recorded. Analyses indicated that the Joint participants outperformed the Solo participants in the ability to synchronize the spatial and temporal components of their imitation movements with the trainer’s pattern-modeling movements. The same group showed superior performance when attempting to freely produce the pattern. These results carry significant theoretical and translational potentials for the fields of motor learning and rehabilitation.
ContributorsSoliman, Tamer (Author) / Glenberg, Arthur (Thesis advisor) / Helms Tillery, Stephen (Committee member) / McBeath, Michael (Committee member) / Amazeen, Eric (Committee member) / Arizona State University (Publisher)
Created2015