Clinical trial NCT05611788: Structure Learning Training and Cognitive Flexibility
Official title: Structure Learning Training and Cognitive Flexibility
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Healthy
Keywords: Structure Learning
Cognitive Flexibility
Neural Activation
Intervention
Predictive statistics
Lead sponsor: Nanyang Technological University
Sponsor class: OTHER
Collaborators: name: University of Cambridge
First posted: 2022-11-10
Enrollment: 108
Sex: ALL
Minimum age (years): 18
Maximum age (years): 55
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: Participants are pseudo-randomly assigned (matched for age, sex, intelligence and flexibility) to one of the following intervention groups: (1) Structure Learning and (2) No training (Passive Control)
Primary purpose: BASIC_SCIENCE

Brief summary: The overarching aim of the project is to assess whether structure learning is an effective tool to train and improve cognitive flexibility and whether this is transferable to learning and other cognitive skills. The investigators will employ a multi-modal approach that combine both cognitive-behavioural and neuroimaging measures to examine how functional brain activations and/or cognitive performances are affected when participants go through a structure learning training paradigm relative to a working memory training paradigm (active control) or a no-training paradigm (passive control).

Detailed description: Cognitive flexibility is critical for humans to perform complex tasks and ensures that humans exhibit appropriate behaviour in response to changing environments. Successful implementation of cognitive flexibility involves several sub-domains within executive functions. Prior researches on cognitive flexibility has portrayed it as various aspects of human cognition ranging from a cognitive skill related to set-shifting, or a by-product of cognitive processes, to part of the cognitive system. The operationalization of cognitive flexibility has been particularly difficult due to its multi-faceted nature. Current flexibility interventions and neuroimaging studies examining cognitive flexibility commonly utilise tasks that taps on to executive functions such as task-set switching or the Dimensional Change Card Sort (DCCS) task. Although effective, one concern related to using these tasks is that it does not tap merely into cognitive flexibility but also activate other executive functions such as inhibition and working memory. Hence, this reduces the precision and specificity of these tasks as training tools. The present project proposed structure learning as a more fundamental and apt training approach. It involves seeking patterns in the stochastic presentations of stimuli, without the need for explicit feedback and is in itself a basic building block for cognitive flexibility.

In the educational context, structure learning is analogous to patterning, a crucial cognitive ability that underpins mathematical and reading skills. Prior research has demonstrated a close relationship between pattern understanding and cognitive flexibility. Hence, structure learning training could potentially be beneficial in improving one's cognitive flexibility. Furthermore, emerging evidence has demonstrated that domain-general training of structure learning skills produced learning that transfer well beyond the learning task. However, there is a paucity in studies that examined whether structure learning training per se could produce generalisable improvements in cognitive flexibility. The present study aims to address this gap by examining if structure learning training, relative to working memory training and having no training, could produce changes in neural markers that relate to potential gains in cognitive flexibility.

Eligibility criteria: Inclusion Criteria:

* Healthy volunteer (male of female) between 18 and 55 years who gave written informed consent to participate

Exclusion Criteria:

* Current and/or prior history of learning disabilities
* Current and/or prior history of neurological disorder
* Current and/or prior history of psychiatric disorder
* Current and/or prior history of cardiovascular disorder
* Predominantly left-handed
* Contraindications for MRI (e.g., pacemakers, implanted pumps, metal objects in the body)
* Claustrophobic
* Pregnancy (females)
* Lactation (females)
* Pronounced visual or auditory impairments

Primary outcomes:
measure: Structure Learning Outcome 1 - Performance Index (PI) Relative
timeFrame: Across two weeks of intervention
measure: Structure Learning Outcome 2 - Strategy choice
timeFrame: Across two weeks of intervention
measure: Structure Learning Outcome 3 - Strategy index (measured by the integral curve difference)
timeFrame: Across two weeks of intervention.
measure: Structure Learning Outcome 4 - Learning rate
timeFrame: Across two weeks of intervention.
measure: Structure Learning Outcome 5 - Strategy shifting rate
timeFrame: Across two weeks of intervention.
measure: Cognitive Flexibility Outcome 1 - Wisconsin Card Sorting Test (WCST): Proportion of perseverative errors
timeFrame: One week after post-MRI scan (post-intervention)
measure: Cognitive Flexibility Outcome 2 - Wisconsin Card Sorting Test (WCST): Learning rate
timeFrame: One week after post-MRI scan (post-intervention)
measure: Cognitive Flexibility Outcome 3 - Wisconsin Card Sorting Test (WCST): Decision consistency
timeFrame: One week after post-MRI scan (post-intervention)
measure: Cognitive Flexibility Outcome 4 - Intra/Extra-Dimensional Set Shifting (IED): Extra-dimensional set errors
timeFrame: One week after post-MRI scan (post-intervention)
measure: Cognitive Flexibility Outcome 5 - Intra/Extra-Dimensional Set Shifting (IED): Extra-dimensional reversal errors
timeFrame: One week after post-MRI scan (post-intervention)
measure: Cognitive Flexibility Outcome 6 - Intra/Extra-Dimensional Set Shifting (IED): Learning rate
timeFrame: One week after post-MRI scan (post-intervention)
measure: Cognitive Flexibility Outcome 7 - Intra/Extra-Dimensional Set Shifting (IED): Choice determinism
timeFrame: One week after post-MRI scan (post-intervention)
measure: Cognitive Flexibility Outcome 8 - Intra/Extra-Dimensional Set Shifting (IED): Dimension primacy
timeFrame: One week after post-MRI scan (post-intervention)
measure: Cognitive Flexibility Outcome 9 - Probabilistic Reversal Learning (PRL): Perseveration
timeFrame: One week after post-MRI scan (post-intervention)
measure: Cognitive Flexibility Outcome 10 - Probabilistic Reversal Learning (PRL): Switch probability
timeFrame: One week after post-MRI scan (post-intervention)
measure: Cognitive Flexibility Outcome 11 - Probabilistic Reversal Learning (PRL): Trials to criterion in block 2 (Reversal)
timeFrame: One week after post-MRI scan (post-intervention)
measure: Cognitive Flexibility Outcome 12 - Probabilistic Reversal Learning (PRL): Learning rates
timeFrame: One week after post-MRI scan (post-intervention)
measure: Cognitive Flexibility Outcome 13 - Probabilistic Reversal Learning (PRL): Reinforcement sensitivity
timeFrame: One week after post-MRI scan (post-intervention)
measure: Cognitive Flexibility Outcome 14 - Probabilistic Reversal Learning (PRL): Stickiness
timeFrame: One week after post-MRI scan (post-intervention)
measure: Cognitive Flexibility Outcome 15 - Task Set Switching - Where (TSS-Where): Task switch cost in RT
timeFrame: One week after post-MRI scan (post-intervention)
measure: Cognitive Flexibility Outcome 16 - Task Set Switching - Where (TSS-Where): Task switch cost in Accuracy
timeFrame: One week after post-MRI scan (post-intervention)
measure: Cognitive Flexibility Outcome 17 - Task Set Switching - What (TSS-What): Task switch cost in RT
timeFrame: One week after post-MRI scan (post-intervention)
measure: Cognitive Flexibility Outcome 18 - Task Set Switching - What (TSS-What): Task switch cost in Accuracy
timeFrame: One week after post-MRI scan (post-intervention)
measure: Cognitive Flexibility Outcome 19 - Colour Shape Task (CST): Task switch cost in RT
timeFrame: Baseline (pre-intervention)
measure: Cognitive Flexibility Outcome 20 - Colour Shape Task (CST): Task switch cost in Accuracy
timeFrame: Baseline (pre-intervention)
measure: Cognitive Flexibility Outcome 21 - Colour Shape Task (CST): Task switch cost in RT
timeFrame: One week after post-MRI scan (post-intervention)
measure: Cognitive Flexibility Outcome 22 - Colour Shape Task (CST): Task switch cost in Accuracy
timeFrame: One week after post-MRI scan (post-intervention)
measure: Cognitive Flexibility Outcome 23 - Colour Shape Task (CST): Change in task switch cost in RT
timeFrame: Baseline (pre-intervention) and 8 weeks (after post-MRI scan, post-intervention)
measure: Cognitive Flexibility Outcome 24 - Colour Shape Task (CST): Change in task switch cost in accuracy
timeFrame: Baseline (pre-intervention) and 8 weeks (after post-MRI scan, post-intervention)
measure: Cognitive Flexibility Outcome 25 - Trail Making Test (TMT): Ratio between time to complete Trail B to Trail A
timeFrame: One week after post-MRI scan (post-intervention)
measure: Working Memory Outcome 1 - Backwards Digit Span (BDS): Total items correct
timeFrame: One week after post-MRI scan (post-intervention)
measure: Working Memory Outcome 2 - Reading Span (RS): Number of correctly recalled digits
timeFrame: One week after post-MRI scan (post-intervention)
measure: Working Memory Outcome 3 - Spatial Working Memory (SWM): Between search errors
timeFrame: One week after post-MRI scan (post-intervention)
measure: Working Memory Outcome 4 - Spatial Working Memory (SWM): Strategy score
timeFrame: One week after post-MRI scan (post-intervention)
measure: Inhibition Outcome 1 - Stroop Task: Interference measure for RT
timeFrame: One week after post-MRI scan (post-intervention)
measure: Inhibition Outcome 2 - Stroop Task: Interference measure for accuracy
timeFrame: One week after post-MRI scan (post-intervention)
measure: Inhibition Outcome 3 - Stop Signal Task (SST): Probability of Go responses on Stop trials
timeFrame: One week after post-MRI scan (post-intervention)
measure: Inhibition Outcome 4 - Stop Signal Task (SST): Stop Signal Reaction Time
timeFrame: One week after post-MRI scan (post-intervention)
Secondary outcomes:
measure: Perceived Stress Outcome 1 - Perceived Stress Scale (PSS): Perceived Stress Scale Score
timeFrame: One week after post-MRI scan (post-intervention)
measure: Sleep Quality Outcome 1 - Pittsburgh Sleep Quality Index (PSQI): Global PSQI Score
timeFrame: One week after post-MRI scan (post-intervention)
measure: Empathy Outcome 1 - Empathy Quotient (EQ): Empathy Quotient Score
timeFrame: Baseline (pre-intervention) and 8 weeks (after post-MRI scan, post-intervention)
measure: Language and Numeracy Outcome 1 - Woodcock Johnson IV (WJIV): Scores from Test 1 Letter-Word Identification
timeFrame: One week before pre-MRI scan (pre-intervention)
measure: Language and Numeracy Outcome 2 - Woodcock Johnson IV (WJIV): Scores from Test 2 Applied Problems
timeFrame: One week before pre-MRI scan (pre-intervention)
measure: Language and Numeracy Outcome 3 - Woodcock Johnson IV (WJIV): Scores from Test 4 Passage Comprehension
timeFrame: One week before pre-MRI scan (pre-intervention)
measure: Language and Numeracy Outcome 4 - Woodcock Johnson IV (WJIV): Scores from Test 5 Calculation
timeFrame: One week before pre-MRI scan (pre-intervention)
measure: Language and Numeracy Outcome 5 - Woodcock Johnson IV (WJIV): Scores from Test 9 Sentence Reading Fluency
timeFrame: One week before pre-MRI scan (pre-intervention)
measure: Language and Numeracy Outcome 6 - Woodcock Johnson IV (WJIV): Scores from Test 10 Maths Fact Fluency
timeFrame: One week before pre-MRI scan (pre-intervention)
measure: Social Decision Making Outcome 1 - Social Value Orientation: Weighted average
timeFrame: Baseline (pre-intervention) and 8 weeks (after post-MRI scan, post-intervention)
measure: Social Decision Making Outcome 2 - Prisoner's Dilemma: Proportion of cooperative choices
timeFrame: Baseline (pre-intervention) and 8 weeks (after post-MRI scan, post-intervention)
measure: Social Decision Making Outcome 3 - Trust Game: Trust preference
timeFrame: Baseline (pre-intervention) and 8 weeks (after post-MRI scan, post-intervention)
measure: Social Decision Making Outcome 4 - Trust Game: Proportion of trust choices
timeFrame: Baseline (pre-intervention) and 8 weeks (after post-MRI scan, post-intervention)
measure: Social Decision Making Outcome 5 - Trust Game: Proportion of cooperative choices
timeFrame: Baseline (pre-intervention) and 8 weeks (after post-MRI scan, post-intervention)
measure: Social Decision Making Outcome 6 - Risk Preference: Risk Preference (Positive)
timeFrame: Baseline (pre-intervention) and 8 weeks (after post-MRI scan, post-intervention)
measure: Social Decision Making Outcome 7 - Ambiguity Aversion: Ambiguity preference
timeFrame: Baseline (pre-intervention) and 8 weeks (after post-MRI scan, post-intervention)
measure: Social Decision Making Outcome 8 - Personal Relative Deprivation Scale: Total personal relative deprivation score
timeFrame: Baseline (pre-intervention) and 8 weeks (after post-MRI scan, post-intervention)
measure: Social Decision Making Outcome 9 - Cooperativeness and Competitiveness Personality Scale: Score for Cooperativeness dimension
timeFrame: Baseline (pre-intervention) and 8 weeks (after post-MRI scan, post-intervention)
measure: Social Decision Making Outcome 10 - Cooperativeness and Competitiveness Personality Scale: Score for Competitiveness dimension
timeFrame: Baseline (pre-intervention) and 8 weeks (after post-MRI scan, post-intervention)
measure: Tolerance of Uncertainty Outcome 1 - Receptiveness to Opposing Views: Score from Questionnaire
timeFrame: Baseline (pre-intervention) and 8 weeks (after post-MRI scan, post-intervention)
measure: Tolerance of Uncertainty Outcome 2 - Need for Closure Scale: Score from Questionnaire
timeFrame: Baseline (pre-intervention) and 8 weeks (after post-MRI scan, post-intervention)
measure: Tolerance of Uncertainty Outcome 3 - Curiosity and Exploration: Score from Questionnaire
timeFrame: Baseline (pre-intervention) and 8 weeks (after post-MRI scan, post-intervention)
measure: Tolerance of Uncertainty Outcome 4 - Racial Essentialism Scale: Score from Questionnaire
timeFrame: Baseline (pre-intervention) and 8 weeks (after post-MRI scan, post-intervention)
measure: Multilingualism Outcome 1 - Clip-Q Singapore Language History Questionnaire: Score from Questionnaire
timeFrame: One week after post-MRI scan (post-intervention)
measure: Perceived Social Support Outcome 1 - Multidimensional Scale of Perceived Social Support: Score from Questionnaire
timeFrame: One week after post-MRI scan (post-intervention)
measure: Personality Outcome 1 - Big Five Inventory: Score from Questionnaire
timeFrame: One week after post-MRI scan (post-intervention)
measure: Imaging Outcome 1 - GABA+ levels in left DLPFC
timeFrame: At pre-MRI scan (pre-intervention) and at post-MRI scan with minimum two-weeks interval (post-intervention)
measure: Imaging Outcome 2 - GABA+ levels in right DLPFC
timeFrame: At pre-MRI scan (pre-intervention) and at post-MRI scan with minimum two-weeks interval (post-intervention)
measure: Imaging Outcome 3 - Resting-state functional magnetic imaging (rsfMRI): Whole brain search analysis (beta value)
timeFrame: At pre-MRI scan (pre-intervention) and at post-MRI scan with minimum two-weeks interval (post-intervention)
measure: Imaging Outcome 4 - Resting-state functional magnetic imaging (rsfMRI): Region of interest (ROI) based analysis (beta value)
timeFrame: At pre-MRI scan (pre-intervention) and at post-MRI scan with minimum two-weeks interval (post-intervention)
measure: Imaging Outcome 5 - Resting-state functional magnetic imaging (rsfMRI): Group independent component (group ICA) analysis (weighted component score)
timeFrame: At pre-MRI scan (pre-intervention) and at post-MRI scan with minimum two-weeks interval (post-intervention)
measure: Imaging Outcome 6 - Resting-state functional magnetic imaging (rsfMRI): Functional connectivity analysis
timeFrame: At pre-MRI scan (pre-intervention) and at post-MRI scan with minimum two-weeks interval (post-intervention)
measure: Imaging Outcome 7 - Multiparameter mapping (MPM): Whole brain voxel-based quantification analyses
timeFrame: At pre-MRI scan (pre-intervention) and at post-MRI scan with minimum two-weeks interval (post-intervention)
measure: Imaging Outcome 8 - Multiparameter mapping (MPM): ROI analyses
timeFrame: At pre-MRI scan (pre-intervention) and at post-MRI scan with minimum two-weeks interval (post-intervention)
measure: General Intelligence Outcome 1 - Raven's Advanced Progressive Matrices (RAPM): Total correct
timeFrame: Baseline (pre-intervention)
measure: General Intelligence Outcome 2 - Raven's Advanced Progressive Matrices (RAPM): Change in accuracy score
timeFrame: Baseline (pre-intervention) and 8 weeks (after post-MRI scan, post-intervention)
measure: General Intelligence Outcome 3 - Wechsler Abbreviated Scale of Intelligence Block Design (WASI-B): Block design score
timeFrame: One week before pre-MRI scan (pre-intervention)
measure: General Intelligence Outcome 4 - Wechsler Abbreviated Scale of Intelligence Vocabulary (WASI-V): Vocabulary score
timeFrame: Baseline (pre-intervention)
measure: Creativity Outcome 1 - Verbal Fluency Test (VFT): Mean fluency score (Category)
timeFrame: One week after post-MRI scan (post-intervention)
measure: Creativity Outcome 2 - Verbal Fluency Test (VFT): Mean fluency score (Letter)
timeFrame: One week after post-MRI scan (post-intervention)
measure: Creativity Outcome 3 - Verbal Fluency Test (VFT): Clustering coefficient
timeFrame: One week after post-MRI scan (post-intervention)
measure: Creativity Outcome 4 - Verbal Fluency Test (VFT): Average shortest path length
timeFrame: One week after post-MRI scan (post-intervention)
measure: Creativity Outcome 5 - Verbal Fluency Test (VFT): Modularity
timeFrame: One week after post-MRI scan (post-intervention)
measure: Creativity Outcome 6 - Alternate Uses Task (AUT): Total fluency score
timeFrame: One week after post-MRI scan (post-intervention)
measure: Creativity Outcome 7 - Alternate Uses Task (AUT): Total originality score
timeFrame: One week after post-MRI scan (post-intervention)
measure: Creativity Outcome 8 - Alternate Uses Task (AUT): Total flexibility score
timeFrame: One week after post-MRI scan (post-intervention)
measure: Creativity Outcome 9 - Remote Associates Test (RAT): Percentage of correct solutions
timeFrame: One week after post-MRI scan (post-intervention)
measure: Creativity Outcome 10 - Creative Mindset: Score from Questionnaire
timeFrame: Baseline (pre-intervention) and 8 weeks (after post-MRI scan, post-intervention)
Other outcomes:
measure: Edinburgh Handedness Inventory Score: Total handedness score
timeFrame: Baseline (pre-intervention)
measure: Mood and State Outcome 1 - Self-Assessment Manikin (SAM)
timeFrame: Daily across two weeks of intervention.
measure: Mood and State Outcome 2 - Self-Assessment Manikin (SAM)
timeFrame: Four weeks from baseline, at pre-mri scan (pre-intervention)
measure: Mood and State Outcome 3 - Self-Assessment Manikin (SAM)
timeFrame: Six weeks from baseline, at post-mri scan (post-intervention)
measure: Mood and State Outcome 4 - Training Feedback: Task enjoyment level
timeFrame: Daily across two weeks of intervention.
measure: Mood and State Outcome 5 - Training Feedback: Task difficulty level
timeFrame: Daily across two weeks of intervention.
measure: Mood and State Outcome 6 - Patient Health Questionnaire-9 (PHQ-9): Total score
timeFrame: One week before pre-MRI scan (pre-intervention)
measure: Mood and State Outcome 7 - Patient Health Questionnaire-9 (PHQ-9): Total score
timeFrame: One week after post-MRI scan (post-intervention)
measure: Mood and State Outcome 8 - Generalized Anxiety Disorder-7 (GAD-7): Total score
timeFrame: One week before pre-MRI scan (pre-intervention)
measure: Mood and State Outcome 9 - Generalized Anxiety Disorder-7 (GAD-7): Total score
timeFrame: One week after post-MRI scan (post-intervention)
Locations:
city: Singapore
country: Singapore
facility: Centre for Lifelong Learning and Individualised Cognition (CLIC), Nanyang Technological University
Study officials:
affiliation: Nanyang Technological University
name: Annabel Chen, PhD
role: PRINCIPAL_INVESTIGATOR
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