Passive attentional capture in the attentional boost effect

The attentional boost effect (ABE) describes an interesting phenomenon in which divided attention enhances memory encoding in dual-task paradigms. While past research has focused on features of the encoded stimuli, less is known about the influence that the attention-capturing target signal exerts. This study examines how implicit learning (through colour priming) might affect the attention-capturing process in the ABE. Sixty-three university students participated in an encoding-recognition experiment involving three different colour conditions. Each condition included a priming phase, an encoding phase, a wash-out period, and a recognition phase. In the priming phase, participants passively viewed images predominantly associated with a specific colour. In the encoding phase, participants performed a dual-task of detecting red target signals (while ignoring green distractor signals) and memorizing words presented in the background. The subsequent recognition test required them to classify words as either old items or new items. Significant differences in ABE magnitude were found across conditions. Red priming (i.e., the same colour as the detection target) elicited the strongest boost, potentially due to enhanced attentional capture through congruent colour priming. Green priming diminished the effect, possibly due to a shift of attention toward the distractors. The yellow control condition yielded an effect that fell between those of the other two conditions. The findings reveal that colour priming can enhance memory encoding by strengthening passive attentional engagement under divided attention conditions and further suggest that preexposure to features of the target signal is critical for this enhancement. From an applied psychology perspective, beyond improving cognitive efficiency, the findings have broader implications for applications in high-memory-load situations. For example, people experiencing memory difficulties may benefit from interventions informed by this study. Integrating dual-task paradigms into game-based therapy may offer a promising way to enhance memory encoding via this effect, particularly in populations such as older adults and students in educational settings.