Nasal Pulse Volume Change in the Concealed Information Test

Abstract

The concealed information test (CIT) assesses an individual’s knowledge of crime-related information by comparing responses to crime-relevant and irrelevant items. Previous research identified a reduction in nasal blood flow for crime-relevant items compared to irrelevant ones. This study aimed to replicate these findings by measuring nasal pulse volume in 16 participants. Additionally, it explored the impact of intentional concealment of the relevant item on nasal pulse volume. Consistent with earlier findings, participants who knew and concealed a relevant item exhibited smaller nasal pulse volumes than those for irrelevant items. However, no significant difference in nasal pulse volume was observed between items after participants disclosed their knowledge of the relevant item. These results suggest that nasal blood volume is reduced for relevant items in the CIT, but this effect appears contingent on the active concealment of knowledge about these items.