Dopaminergic function is a critical transdiagnostic neurophysiological dimension with broad relevance in psychiatry. Normalized T2*-weighted (nT2*w) imaging has been previously investigated as a method to quantify biological properties of tissue in the striatum (e.g., tissue iron), providing a widely available, in vivo marker with potential relevance to dopaminergic function; but no prior study to our knowledge has examined this neuroimaging marker in clinical depression. In a treatment-seeking, clinically depressed sample (n = 110), we quantified tissue iron (nT2*w) in striatal regions. We assessed test-retest reliability and correlated values with dimensional features across levels of analysis, including demographic/biological (sex, age, Body Mass Index), neuroanatomical (hippocampal atrophy, which was quantified using a recently validated machine-learning algorithm), and performance-based (Affective Go/NoGo task performance) indices with relevance to depressive neurocognition. Across patients, decreased tissue iron concentration (as indexed by higher nT2*w) in striatal regions correlated with indices of decreased cognitive-affective function on the Affective Go/NoGo task. Greater caudate nT2*w also correlated with greater hippocampal atrophy. Striatal tissue iron concentrations were robustly lower in female patients than males but gender differences did not explain relations with other neurocognitive variables. A widely available fMRI index of striatal tissue properties, which exhibited strong psychometric properties and can be readily quantified from most fMRI datasets irrespective of study-specific features such as task design, showed relevance to multiple biobehavioral markers of pathophysiology in the context of moderate-to-severe, treatment-resistant depression. Striatal tissue iron may play a role in dimensional and subgroup-specific features of depression, with implications for future research on depression heterogeneity.

多巴胺能功能是一个关键的跨诊断神经生理学维度，与精神病学具有广泛的相关性。归一化 T2* 加权 (nT2*w) 成像先前已被研究作为一种量化纹状体组织（例如，组织铁）生物学特性的方法，提供了一种广泛可用的、与多巴胺能功能具有潜在相关性的体内标记物；但据我们所知，之前没有研究检查过临床抑郁症中的这种神经影像学标记物。在寻求治疗的临床抑郁样本中（n = 110)，我们量化了纹状体区域的组织铁 (nT2*w)。我们评估了重测可靠性和相关值与跨分析级别的维度特征，包括人口统计/生物学（性别、年龄、体重指数）、神经解剖学（海马萎缩，使用最近验证的机器学习算法进行量化），以及基于性能的（情感 Go/NoGo 任务性能）指数与抑郁神经认知相关。在患者中，纹状体区域组织铁浓度降低（由较高的 nT2*w 指示）与情感 Go/NoGo 任务中认知情感功能下降的指数相关。更大的尾状核 nT2*w 也与更大的海马萎缩相关。女性患者的纹状体组织铁浓度明显低于男性，但性别差异并不能解释与其他神经认知变量的关系。一个广泛可用的纹状体组织特性的 fMRI 指数显示出强大的心理测量特性，并且可以很容易地从大多数 fMRI 数据集中量化，而不管研究特定的特征，如任务设计，表明在中度到-严重的、难治性抑郁症。纹状体组织铁可能在抑郁症的维度和亚组特异性特征中发挥作用，对未来抑郁症异质性研究具有重要意义。它表现出很强的心理测量特性，并且可以很容易地从大多数 fMRI 数据集中量化，而不考虑任务设计等特定研究特征，在中度至重度、难治性抑郁症的背景下显示出与病理生理学的多种生物行为标志物的相关性。纹状体组织铁可能在抑郁症的维度和亚组特异性特征中发挥作用，对未来抑郁症异质性研究具有重要意义。它表现出很强的心理测量特性，并且可以很容易地从大多数 fMRI 数据集中量化，而不考虑任务设计等特定研究特征，在中度至重度、难治性抑郁症的背景下显示出与病理生理学的多种生物行为标志物的相关性。纹状体组织铁可能在抑郁症的维度和亚组特异性特征中发挥作用，对未来抑郁症异质性研究具有重要意义。