Yuxuan Zeng¹, Ren E. Hentz¹, David E. Osher¹; ¹The Ohio State University

The debate regarding the origins of holistic processing remains unresolved. Some theories posit that this mechanism is domain-specific to faces, whereas others argue it is a domain-general consequence of expertise. Our previous work challenged the strict face-specific view by demonstrating that learning configural information allows observers to process novel non-face stimuli holistically. However, a critical question remains regarding the role of proficiency. Does holistic processing emerge immediately upon learning a categorization rule, or does it depend on the higher level of proficiency associated with expertise? To investigate this, we trained participants to categorize computer-generated abstract line patterns. In the criterion-based condition, training ceased immediately after participants achieved 90% accuracy in the final 30 trials. The training duration for this group varied from 30 to 180 trials and averaged approximately 100 trials. In the fixed-training condition, participants completed a regimen of 200 trials. We ensured that participants in this group also maintained over 90% accuracy in their final block to match the performance level of the first group. Preliminary results reveal a functional dissociation between the two groups. Participants who stopped immediately upon reaching the accuracy criterion showed limited evidence of holistic processing. We observed a composite effect in this group, which suggests this measure might be particularly sensitive, but we found no significant inversion, misalignment, or part-whole effects. In contrast, the group trained for 200 trials exhibited robust holistic processing across all four measures. These findings indicate that simply learning the categorization rule is insufficient. Instead, the visual system requires a degree of proficiency characteristic of expertise to engage holistic mechanisms. Crucially, our data suggest that for certain tasks, the functional transition from learner to expert does not require years of experience but can occur within a short window of 200 trials.