Nestor Paul G, Levitt James J, Ohtani Toshiyuki, Newell Dominick T, Shenton Martha E, Niznikiewicz Margaret
Department of Psychology, University of Massachusetts, Boston, MA, USA.
Clinical Neuroscience Division, Laboratory of Neuroscience, Department of Psychiatry, Veterans Affairs (VA) Boston Healthcare System, Harvard Medical School, Brockton, MA, USA.
Schizophr Bull Open. 2022 Mar 8;3(1):sgac004. doi: 10.1093/schizbullopen/sgac004. eCollection 2022 Jan.
In 1908, Bleuler proposed a unitary theory of schizophrenia, hypothesizing a "loosening of associations" as the central mechanism underlying disturbances in thinking, motivation, and affective expression. Here, we test Bleuler's model in an archival sample of 79 healthy controls and 76 patients with chronic schizophrenia who had completed neuropsychological tests, including a measure of learning of novel word pairs, which was specifically selected to probe the structure and formation of new verbal associations. The patients also had positive and negative symptoms ratings, including measures of flat affect, anhedonia, and thought disorder. A subset of patients and controls ( = 39) had available prior archival 3-T magnetic resonance imaging (MRI) measures of prefrontal cortex (PFC) gray matter volumes. In relation to controls, patients showed evidence of a selective impairment in associative learning, independent of their overall reduced neuropsychological functioning. This neuropsychological impairment, in turn, correlated significantly with overall levels of negative but not positive symptoms, with the data showing an especially strong contribution of flattened emotional expression to verbal associate learning deficits in this patient sample. Moreover, the archival MRI data were consistent with prior research pointing to an important role of the PFC in supporting verbal associate learning and memory in patients and controls. Taken together, the current results provided evidence of a selective impairment in schizophrenia on a PFC-supported verbal associate learning and memory task, which was accompanied by negative symptoms in general, and flattened emotional expression, in particular.
1908年，布鲁勒提出了一种精神分裂症的统一理论，假设“联想松弛”是思维、动机和情感表达障碍的核心机制。在此，我们在一个存档样本中检验布鲁勒的模型，该样本包括79名健康对照者和76名患有慢性精神分裂症的患者，这些患者完成了神经心理学测试，包括一项新单词对学习的测量，该测量是专门为探究新言语联想的结构和形成而选择的。患者还进行了阳性和阴性症状评分，包括情感平淡、快感缺失和思维障碍的测量。一部分患者和对照者（n = 39）有可用的先前存档的3-T磁共振成像（MRI）测量的前额叶皮质（PFC）灰质体积。与对照者相比，患者表现出联想学习方面的选择性损伤，这与其整体神经心理功能下降无关。这种神经心理损伤反过来又与阴性症状而非阳性症状的总体水平显著相关，数据显示在该患者样本中，情感表达平淡对言语联想学习缺陷有特别强烈的影响。此外，存档的MRI数据与先前的研究一致，表明PFC在支持患者和对照者的言语联想学习和记忆方面具有重要作用。综上所述，目前的结果提供了证据，表明精神分裂症患者在PFC支持的言语联想学习和记忆任务上存在选择性损伤，这种损伤总体上伴有阴性症状，尤其是情感表达平淡。
