The Attentional Boost Effect (ABE) refers to the phenomenon in which target detection during dual-task encoding enhances memory for concurrently presented background information. The dual?task interaction model of ABE proposes that the effect arises when the attentional enhancement triggered by target detection outweighs the interference induced by the dual?task. Subsequently, the ABE paradigm has been extended to various clinical populations, in which the effect is absent. Given the specificity of ABE in these clinical populations, the present study employed the classic ABE paradigm to investigate whether individuals with suicidal exhibit a reduced or absent ABE due to cognitive inhibition deficits, and whether this effect is generalizable across different types of materials.

Two independent experiments were conducted using pictures and words as background stimuli. Both experiments adopted a 2 (group: suicidal individuals, healthy control group) × 3 (trial type: target, distractor, baseline) mixed design, with group as the between-subjects factor and trial type as the within-subjects factor. The experimental procedure consisted of a study phase, a distractor phase, and a test phase. During the study phase, participants were required to memorize a series of sequentially presented background stimuli while concurrently monitoring colored squares presented simultaneously with the stimuli: a red square (target) required a button press, whereas a green square (distractor) or no square (baseline) required no response. Following the study phase, participants immediately completed a 2-minute arithmetic distractor task, after which a recognition memory test (old / new judgment) was administered.

Considering that participants' intelligence and false alarm rates might influence the experimental results, an analysis of covariance (ANCOVA) was conducted using the corrected recognition rate as the dependent variable and intelligence scores as the covariate. Results showed that the healthy control group replicated the classic ABE for both stimulus materials, with recognition memory significantly better under target conditions than under distractor conditions. In contrast, the suicidal group exhibited material-specific dissociation of the ABE: the ABE was absent for picture materials but present for word materials.

The absence of the ABE for picture materials indicates that, due to impaired cognitive inhibition, the individuals with suicidal requires more attentional resources to perform the target detection task, leading the interference effect of dual?task to outweigh the facilitatory effect of attentional enhancement. The presence of the ABE for word suggests that the cognitive deficits in individuals with suicidal tendency are not global. The material specificity may stem from the following factors: (1) pictures have stronger emotional arousal capacity, which can easily trigger a low mood state in individuals with suicidal, thereby exacerbating their cognitive inhibition deficits; (2) word processing relies on top?down phonological and semantic decoding, which allows cognitive control functions to be relatively preserved. It should be noted that the preservation of the ABE in the word experiment does not deny the existence of inhibitory deficits in suicidal individuals; it may be due to relatively low task difficulty. These results suggest that the cognitive processing mechanisms for pictures and words may differ in the individuals with suicidal.

These findings provide a novel perspective on the cognitive characteristics of individuals with suicidal and extend the application of the ABE paradigm in clinical cognitive assessment. Future research should build upon these findings by expanding sample sizes, incorporating multimodal physiological measures, increasing task difficulty, and employing longitudinal designs to further validate and deepen the clinical significance and theoretical implications of this study.