An event-coding account of attitudes

Attitudes (or opinions, preferences, biases, stereotypes) can be considered bindings of the perceptual features of the attitudes’ object to affective codes with positive or negative connotations, which effectively renders them “event files” in terms of the Theory of Event Coding. We tested a particularly interesting implication of this theoretical account: that affective codes might “migrate” from one event file to another (i.e., effectively function as a component of one while actually being part of another), if the two files overlap in terms of other features. We tested this feature-migration hypothesis by having participants categorize pictures of fictitious outer space characters as members of two fictitious races by pressing a left or right key, and to categorize positive and negative pictures of the International Affective Picture System (IAPS) as positive and negative by using the same two keys. When the outer space characters were later rated for likability, members of the race that was categorized by means of the same key as positive IAPS pictures were liked significantly more than members of the race that was categorized with the same key as negative IAPS pictures – suggesting that affective feature codes from the event files for the IAPS pictures effectively acted as an ingredient of event files for the outer space characters that shared the same key. These findings were fully replicated in a second experiment in which the two races were replaced by two unfamiliar fonts. These outcomes are consistent with the claim that attitudes, opinions, and preferences are represented in terms of event files and created by feature binding.

Mind wandering at encoding, but not at retrieval, disrupts one-shot stimulus-control learning

The one-shot pairing of a stimulus with a specific cognitive control process, such as task switching, can bind the two together in memory. The episodic control-binding hypothesis posits that the formation of temporary stimulus-control bindings, which are held in event-files supported by episodic memory, can guide the contextually appropriate application of cognitive control. Across two experiments, we sought to examine the role of task-focused attention in the encoding and implementation of stimulus-control bindings in episodic event-files. In Experiment 1, we obtained self-reports of mind wandering during encoding and implementation of stimulus-control bindings. Results indicated that, whereas mind wandering during the implementation of stimulus-control bindings does not decrease their efficacy, mind wandering during the encoding of these control-state associations interferes with their successful deployment at a later point. In Experiment 2, we complemented these results by using trial-by-trial pupillometry to measure attention, again demonstrating that attention levels at encoding predict the subsequent implementation of stimulus-control bindings better than attention levels at implementation. These results suggest that, although encoding stimulus-control bindings in episodic memory requires active attention and engagement, once encoded, these bindings are automatically deployed to guide behavior when the stimulus recurs. These findings expand our understanding of how cognitive control processes are integrated into episodic event files.

Watching the Brain as It (Un)Binds: Beta Synchronization Relates to Distractor–Response Binding

Human action control relies on event files, that is, short-term stimulus–response bindings that result from the integration of perception and action. The present EEG study examined oscillatory brain activities related to the integration and disintegration of event files in the distractor–response binding (DRB) task, which relies on a sequential prime–probe structure with orthogonal variation of distractor and response relations between prime and probe. Behavioral results indicated a DRB effect in RTs, which was moderated by the duration of the RSI between prime response and probe stimulus onset. Indeed, a DRB effect was observed for a short RSI of 500 msec but not for a longer RSI of 2000 msec, indicating disintegration of event files over time. EEG results revealed a positive correlation between individual DRB in the RSI-2000 condition and postmovement beta synchronization after both prime and probe responses. Beamformer analysis localized this correlation effect to the middle occipital gyrus, which also showed highest coherency with precentral and inferior parietal brain regions. Together, these findings suggest that postmovement beta synchronization is a marker of event file disintegration, with the left middle occipital gyrus being a hub region for stimulus–response bindings in the visual DRB task.

Watching the brain as it binds: Beta synchronization relates to distractor-response binding

Human action control relies on event files, i.e., short-term stimulus-response bindings that result from the integration of perception and action. The present electroencephalography (EEG) study examined oscillatory brain activities related to the integration and disintegration of event files in the distractor-response binding (DRB) task, which relies on a sequential prime-probe structure with orthogonal variation of distractor and response relations between prime and probe. Behavioral results indicated a DRB effect in reaction times (RT), which was moderated by the duration of the response-stimulus interval (RSI) between prime response and probe stimulus onset. Indeed, a DRB effect was observed for a short RSI of 500 ms but not for a longer RSI of 2000 ms, indicating disintegration of event files over time. EEG results revealed a positive correlation between individual DRB in the RSI-2000 condition and post-movement beta synchronization after both prime and probe responses. Beamformer analysis localized this correlation effect to the middle occipital gyrus, which also showed highest coherency with precentral and inferior parietal brain regions. Together, these findings suggest that post-movement beta synchronization is a marker of event-file disintegration, with the left middle occipital gyrus being a hub region for stimulus-response bindings in the present visual DRB task.

Temporal persistence of after-effects in the n-1 replication task

In line with the theory of event coding, many studies on tool use show that perceived visual and haptic information interacts with action execution. In two experiments, we investigated the temporal persistence of after-effects within an event file, and after-effects in temporally overlapping event files with the n-1 replication task. Each trial consisted of two phases: In phase 1, participants moved a cursor with a pen on a covered tablet while a gain varied the relation between hand and cursor amplitude (Experiment 1). In phase 2, participants replicated the hand amplitude of phase 1 of the previous trial without visual feedback. Any systematic over- and undershoot would be indicative for after-effects. When the cursor amplitude varied and the hand amplitude remained constant, we did not find any after-effects but adjustment of the internal model. For varying hand amplitudes, after-effects appeared in terms of a contrast and assimilation effect between temporally overlapping event files and within an event file, respectively. In Experiment 2, we confirmed that the observed pattern of over- and undershoots fully reflect assimilation/contrast due to perception-action interaction. The findings extend the current view on the temporal stability of short-term binding in sensorimotor transformation tasks: In the n-1 replication task, after-effects appeared only in trials with varying hand amplitudes. We replicated the contrast effect and assimilation effect, and the assimilation effect persisted for up to approximately 20 s.

Pathophysiologie des Gilles-de-la-Tourette-Syndroms

ZUSAMMENFASSUNGBeim Gilles-de-la-Tourette-Syndrom (GTS) handelt es sich um eine häufige facettenreiche, typischerweise im Kindes- oder Jugendalter beginnende neuropsychiatrische Erkrankung. Die Pathophysiologie ist nicht sicher geklärt. Eine wichtige Rolle scheinen die Basalganglien und kortiko-striato-thalamo-kortikale Regelkreise einzunehmen. Eine der konstantesten Veränderungen stellt eine diskrete Volumenreduktion des Striatums bei Kindern dar. Auch konnten Veränderungen im Bereich der weißen Substanz innerhalb dieses Regelkreises nachgewiesen werden. Auf kortikaler Ebene wurden Veränderungen im Bereich des sensomotorischen und präfrontalen Kortex, der supplementär motorischen Region und des inferioren parietalen Kortex (BA 40) beschrieben. Auf biochemischer Ebene zeigt sich vor allem eine erhöhte dopaminerge Transmission. Auch Serotonin scheint durch den Wegfall Dopamin hemmender Effekte eine Rolle zu spielen. Kognitionspsychologische bzw. wahrnehmungspsychologische Ansätze gingen zunächst von einer gestörten inhibitorischen Kontrolle aus.Aufgrund uneinheitlicher Ergebnisse wird eher eine Interferenz mit Kompensationsmechanismen zur Tic-Kontrolle vermutet. Auch zeigen sich Veränderungen der interozeptiven Wahrnehmung. Allerdings ist unsicher, ob diese ursächlich sind oder eine sekundäre Veränderung des GTS darstellen. Einer der aktuellsten Ansätze stützt sich auf die „Theory of Event Coding“, welche besagt, dass sowohl Wahrnehmungen als auch Handlungen gemeinsam in „event files“ gespeichert werden und in enger Verbindung stehen. Es gibt erste experimentelle Hinweise, dass bei Patienten mit einem GTS die Kopplung zwischen Wahrnehmung und Handlung besonders stark ausgeprägt ist und Tics aufgrund dieser starken Bindung durch verschiedene Stimuli ausgelöst werden könnten.

Gilles de la Tourette Syndrome

Gilles de la Tourette syndrome is a common, multifaceted neuropsychiatric disorder characterized by multiple motor and vocal tics. Although numerous neuroanatomical and neurophysiological particularities have been documented, there is no general concept or overarching theory to explain the pathophysiology of Tourette syndrome. Given the premonitory urges that precede tics and the altered sensorimotor processing in Tourette syndrome, the “Theory of Event Coding” (TEC) seems to be an attractive framework. TEC assumes that perceptions and actions are bound together and encoded using the same neural code to form so-called “event files.” Depending on the strength of the binding between perception and action, partial repetition of features of an event file can lead to increasing cost because existing event files need to be reconfigured. This is referred to as “partial repetition costs”, which appear to be increased in Tourette patients. This indicates stronger binding within “event files” in Tourette.

Conjunctive Representations that Integrate Stimuli, Responses, and Rules are Critical for Action Selection

People can use abstract rules to flexibly configure and select actions for specific situations. Yet how exactly rules shape actions towards specific sensory and/or motor requirements remains unclear. One possibility is that rules become integrated with sensory/response features in a non-linear, conjunctive manner (e.g., event files; Hommel, 1998) to drive rule-guided action selection. To dynamically track such conjunctive representations during action selection, we applied a time-resolved representational similarity analysis to the spectral-temporal profiles of the EEG signal, while participants selected actions based on varying rules. Across two experiments, we found that action selection engages conjunctive representations binding action rules to specific sensory/motor settings throughout the entire selection period. The strength of conjunctions was the most important predictor of trial-by-trial variability in response times (RTs) and was closely, and selectively, related to an important behavioral indicator of event files—the partial-overlap priming pattern. Thus, conjunctive representations were functionally dissociated from their constituent action features and play a critical role during flexible selection of action.