Tag: Ulrich Mayr

The Role of Verbalization in Hierarchical Control

Presenter: Emily Stutz – Psychology

Faculty Mentor(s): Melissa Moss, Ulrich Mayr

Session: (In-Person) Poster Presentation

 Performing complex tasks usually requires the cognitive system to handle rules at multiple levels of abstraction, where lower-level rules depend on the status of higher-level rules (e.g., a child may be allowed to eat with her fingers at home, but use silverware in a restaurant). Previous work has identified verbalization (“inner speech”) as critical for such hierarchical control in the context of situations that require following a sequential plan. However, this work did not assess the need for inner speech in the context of non-serial, or cue-based tasks. Further, only relatively simple, two-level hierarchical control sequences were used. The current study used articulatory suppression to assess whether verbalization is important when handling complex serial-order and cue-based hierarchical tasks. Participants executed tasks with one, two, or three levels of either cue-based rule complexity or sequence complexity, while performing a secondary task that manipulated verbalization demands (articulatory suppression versus foot-tapping). Surprisingly and contrary to previous findings, we did not find a decrease in performance in either the cue-based or the sequential tasks with articulatory suppression. These results seem to indicate that hierarchical control does not require inner speech. Potential reasons for the discrepancy with the previous literature results are discussed.

Does the breathing cycle modulate the orientation of our attention?

Presenter: Nayantara Arora − Neuroscience

Faculty Mentor(s): Ulrich Mayr, Domink Graetz

(In-Person) Poster Presentation

At any point in time, individuals either orient themselves to the outside world, or rely on their internal representations (i.e., memories) to guide behavior and actions. We investigated to what degree the respiratory cycle modulates spontaneous exploration of the environment. Specifically, we tested the hypothesis that the tendency to direct attention to an external cue for information is increased during inhalation and decreased during exhalation. Our research utilized a novel task-switching paradigm that assesses how participants decide between internal and external representations to guide action. Employing eye-tracking, we tracked when people turn to the environment for information while registering respiration using a chest belt. Contrary to the hypothesis, we found that participants tend to orient their attention internally during inhalation and are more likely to check external cues during exhalation. These findings are discussed using evidence from neuroscience into account. To our knowledge, this experiment is the first to examine the relationship between breathing and attentional shifts between internal and external stimuli. Our results demonstrate the coupling of higher-level cognitive functions with lower-level physiological oscillatory signals that are often considered noise. They also pave the way for the examination of the kind of breathing/cognition interactions that are often assumed in the context of meditative practices.

Brain Training and Cognitive Aging: A Meta-analytic Review

Presenter: Lauren Williams

Co-Presenters: Selina Robson

Mentor: Ulrich Mayr

Poster: 35

Major: Psychology

Cognitive decline is an unfortunate hallmark of aging. Deficits can interfere with daily activities and often come at the cost of living independently. In recent years, “brain training” programs and games have become a popular option for older adults who are looking to sharpen their cognitive skills. However, despite their commercial success, it is not clear to what degree these programs produce generalized effects beyond improvement on the trained skills. To determine the size of generalized training effects, we conducted a meta-analysis of existing training studies that used plasticity-focused practice regimes. Studies were included if they sampled adults aged 50 and older, participants had no cognitive impairment, and they had a control group. This led to a final sample of 32 studies. Preliminary results suggest a small-to-moderate overall effect size. In addition, we found that the effect size declined along the near-to-far transfer continuum as assessments become more dissimilar to training type, and with the sample size of the study. Particularly surprising is the fact that the effect size is negatively correlated with duration of the practice regimen. For far-transfer outcome measures with large sample sizes and long durations of practice, the effect size approaches zero. These results raise doubts about the promise that plasticity-related training regimes effectively counter the broad effects of cognitive aging.

The Role of Abstract Chunk Patterns in the Organization of Complex Sequences

Presenter(s): Min Zhang

Faculty Mentor(s): Ulrich Mayr & Melissa Moss

Poster 111

 Session: Social Sciences & Humanities

In order to execute complex sequences, such as playing a piece of music, people group sequential elements (e.g., individual notes) into “chunks”. The dominant theory assumes that chunks are merely independent bundles of elements (Lashley, 1951), though little is known about the organization of chunked information. Applying the efficient coding principle, chunks may be coded in a relational manner, based on structural similarities, to allow people to smoothly execute complex tasks (Botvinick et al., 2015). In two experiments, we assessed how performance is affected by whether chunks contain similar, abstract patterns of elements (“matching” chunks, e.g., ABA pattern of elements in both chunks). Participants completed a task in which they needed to remember and execute sequences of rules. The rule sequences contained two 3-element chunks with various patterns of rule elements. Some sequences contained matching chunks, while others contained non-matching chunks. In Experiment 1, participants executed sequences in which both chunks contained the same types of rules arranged in matching or non-matching patterns. In Experiment 2, the two chunks contained different sets of rules, thus requiring a greater degree of abstraction across chunks. Results showed better performance for sequences containing matching chunks. The effect of pattern similarity on sequential performance was much weaker in Experiment 2 than in Experiment 1. Generally, these findings indicate that our cognitive system makes use of abstract patterns to efficiently code sequential information.

Is Forgetting Good for Learning? Examining the Emergence of Abstract Rule Representations

Presenter(s): Tuong Vy Tran

Faculty Mentor(s): Ulrich Mayr & Atsushi Kikumoto

Poster 131

Session: Social Sciences & Humanities

Most actions are driven by abstract action rules that need to be applied to specific environmental conditions. The abstract goal to make coffee is implemented differently in your own than in your office kitchen. We examine here the degree to which improvements through practice result from (1) strengthened representations of abstract rules, from (2) better adaptation to specific environmental conditions, or from (3) representations that integrate abstract rules and specific conditions into conjunctive representations. We used a task that required the application of up to four different abstract spatial translation rules in order to respond to a given spatial stimulus. Subjects (N=46) performed an initial, 45-minute session applying two of the four rules to one of two possible stimulus configurations. During the second, 45-minute session, the two withheld abstract rules and the second stimulus configuration were introduced. To test the possibility that abstract, generalizable knowledge is fostered through consolidation or forgetting of specific conjunctive representations the second session occurred either right after the first session, or one week apart. Results showed that it was harder to apply new rules to practiced than to new stimulus configurations–– a clear indication conjunctive representations between abstract rules and stimulus settings. Importantly, this effect was substantially weakened when the new rules/stimulus settings were tested after one week. This suggests that during the 1-week delay, specific conjunctive representations were weakened (i.e., forgetting), thereby increasing the contributions of abstract rule representations. In other words, forgetting can benefit the emergence of generalizable skills.

Is Inhibition Dependent on Working Memory Capacity?

Presenter(s): Jena Kunimune

Faculty Mentor(s): Ulrich Mayr & Melissa Moss

Poster 93

Session: Social Sciences & Humanities

The ability to stop initiated actions is a critical component of effective self-regulation, such as resisting the urge for ‘sex, drugs, and rock and roll.’ The current dominant theory in cognitive control assumes that maintaining task-relevant information in working memory is necessary for the effective implementation of inhibitory control. In this study, we addressed the interplay of inhibitory control and working memory maintenance processes using a dual-task paradigm in which both inhibitory control demands and working memory load were manipulated. Because the standard theory predicts mutual interference between the two processes, we hypothesized that if inhibition interferes with working memory maintenance, working memory performance will be lower when participants successfully employ inhibitory control in response to a stop signal, versus when they fail to inhibit their action. Further, this interference in performance should be greatest when working memory load is high. Participants completed a combined working memory and stopping task in which stopping behavior occurred during the working memory maintenance interval. Our results showed no evidence of mutual interference between working memory load and stopping behavior on working memory performance. This result is inconsistent with the dominant view of working memory capacity as the primary constraining factor in inhibitory control. Rather, distinct processing resources may underlie these two different aspects of self-regulation.