Individual differences in higher-level cognitive abilities do not predict overconfidence in complex task performance

Impulsivity Relates to Multi-Trial Choice Strategy in Probabilistic Reversal Learning

Impulsivity is defined as a trait-like tendency to engage in rash actions that are poorly thought out or expressed in an untimely manner. Previous research has found that impulsivity relates to deficits in decision making, in particular when it necessitates executive control or reward outcomes. Reinforcement learning (RL) relies on the ability to integrate reward or punishment outcomes to make good decisions, and has recently been shown to often recruit executive function; as such, it is unsurprising that impulsivity has been studied in the context of RL. However, how impulsivity relates to the mechanisms of RL remains unclear. We aimed to investigate the relationship between impulsivity and learning in a reward-driven learning task with probabilistic feedback and reversal known to recruit executive function. Based on prior literature in clinical populations, we predicted that higher impulsivity would be associated with poorer performance on the task, driven by more frequent switching following unrewarded outcomes. Our results did not support this prediction, but more advanced, trial-history dependent analyses revealed specific effects of impulsivity on switching behavior following consecutive unrewarded trials. Computational modeling captured group-level behavior, but not impulsivity results. Our results support previous findings highlighting the importance of sensitivity to negative outcomes in understanding how impulsivity relates to learning, but indicate that this may stem from more complex strategies than usually considered in computational models of learning. This should be an important target for future research.

Selecting, Administering, and Interpreting Outcome Measures among Adults with Lower-Limb Loss: An Update for Clinicians

Purpose of review

To summarize outcome measurement research among adults with lower-limb loss (LLL) for clinicians.

Recent findings

Houghton Scale, Prosthetic Evaluation Questionnaire-mobility subscale (PEQ-m), Prosthetic Limb Users Survey of Mobility (PLUS-M™), Activities-Specific Balance Confidence Scale (ABC), Amputee Mobility Predictor (AMP), Comprehensive High-Level Activity Mobility Predictor, Four Square Step Test (FSST), Narrowing Beam Walking Test (NBWT), L Test, 10 Meter Walk Test (10MWT), and 6 Minute Walk Test (6MWT) are appropriate for evaluating individual patient changes post-LLL. Post-LLL, Socket Comfort Score, Patient-Specific Functional Scale, Patient-Reported Outcomes Measurement Information System 29-Item Profile, Timed Up and Go, and 2 Minute Walk Test may be more appropriate for evaluating groups. Minimal detectable change is available for 15/20 reviewed measures. Many measures differ between mobility levels.

Summary

Quick, reliable measures for evaluating patient functional change include ABC, PEQ-m, PLUS-M™, FSST, and L Test; when resources allow, NBWT, 10MWT, 6WMT and AMP may be considered.