Understanding the Cognitive Demands of the Purdue Pegboard Test: An fNIRs Study

To evaluate manual dexterity in clinical settings Purdue Pegboard test (PPT) is widely used and consists of four uni- and bi-manual sub-tests. The objective of this study is to deep dive into PPT and parse out the cognitive component of the subtests using functional Near Infrared Spectroscopy (fNIRS). The prefrontal cortex (PFC) of 16 participants was assessed using fNIRS technique while performing PPT. Repeated measures one-way ANOVA was performed on average ∆HbR and ∆HbO in PFC regions (left DLPFC, left vmPFC, right vmPFC, right DLPFC). A Bonferroni correction was used to account for multiple comparisons. Results from both outcome measures taken together showed that assembly sub-task uses significantly higher resources in the left PFC. The findings can be summarized as follows: PPT measures more than manual dexterity. Subtask complexity affects the cognitive demands in the PFC. The Assembly may be the most sensitive subtest to the changes in PFC activity.