Department of Psychology, Florida State University, Tallahassee, Florida.
Department of Psychology, Auburn University, Auburn, Alabama.
Biol Psychiatry Cogn Neurosci Neuroimaging. 2019 Oct;4(10):902-912. doi: 10.1016/j.bpsc.2019.05.015. Epub 2019 Jun 5.
Existing research suggests that inhibitory control deficits may differentiate individuals who think about suicide from those who make a suicide attempt. However, no available research, to our knowledge, has examined whether suicidal behaviors are associated with disruptions in the ability to determine when inhibitory control is needed or the ability to engage inhibition of an inappropriate or maladaptive behavior. The current study utilized event-related potentials to investigate specific facets of inhibitory control and their associations with suicide attempt history among a heterogeneous clinical sample who reported current suicidal ideation.
Ideators with no past suicide attempts (n = 46) and those with a history of suicide attempts (n = 22) completed a complex go/no-go task. Raw waveforms and temporospatial principal components analysis were used to index conflict detection (i.e., ΔN2) and motor inhibition (i.e., ΔP3a). Behavioral performance indices were also examined.
Suicide attempters exhibited deficits in detecting the need for inhibitory control, as indexed by a more positive ΔN2 factor, than did ideating nonattempters, even when accounting for psychiatric comorbidity and age. However, these results only emerged in the principal components analysis-derived latent factor. No differences in behavioral performance or ΔP3a amplitude emerged.
A relative inability to detect when to inhibit a maladaptive behavior, but not the ability to engage motor inhibition to stop that behavior, may distinguish suicide ideators who make a suicide attempt from those who do not. However, future research with prospective designs are needed to determine how conflict detection deficits may contribute to the emergence or escalation of a suicidal crisis.
现有研究表明，抑制控制缺陷可能将思考自杀的人与试图自杀的人区分开来。然而，据我们所知，尚无研究探讨自杀行为是否与确定何时需要抑制控制的能力或抑制不适当或适应不良行为的能力受损有关。本研究利用事件相关电位来研究抑制控制的特定方面及其与有自杀企图史的异质临床样本中当前自杀意念的关系。
无既往自杀企图的意念者（n=46）和有自杀企图史的意念者（n=22）完成了一项复杂的 Go/No-go 任务。原始波形和时空间主成分分析用于指标冲突检测（即ΔN2）和运动抑制（即ΔP3a）。还检查了行为表现指标。
自杀企图者在检测抑制控制需求方面表现出缺陷，表现为更积极的ΔN2 因子，而有自杀意念但无自杀企图的人则表现出缺陷，即使考虑到精神病合并症和年龄也是如此。然而，这些结果仅在主成分分析衍生的潜在因子中出现。在行为表现或ΔP3a 幅度上没有差异。
相对无法检测何时抑制不适当的行为，而不是无法采取运动抑制来阻止该行为，可能将试图自杀的自杀意念者与未尝试自杀的人区分开来。然而，需要进行前瞻性设计的未来研究来确定冲突检测缺陷如何导致自杀危机的出现或升级。
