Ramsay Ian S, Nienow Tasha M, MacDonald Angus W
University of Minnesota Department of Psychology.
Minneapolis VA Health Care System.
Biol Psychiatry Cogn Neurosci Neuroimaging. 2017 May;2(4):355-362. doi: 10.1016/j.bpsc.2016.11.001.
Thalamic projections to the prefrontal cortex (PFC) are critical for cognition, and disruptions in these circuits are thought to underlie the pathophysiology of schizophrenia. Cognitive remediation (REM) is a behavioral intervention that holds promise for improving cognition and functioning in schizophrenia, however the extent to which it affects thalamo-prefrontal connections has not been researched. This study sought to determine whether patients with schizophrenia who undergo a placebo-controlled trial of REM show increased functional connectivity between the thalamus and PFC, and whether these changes correspond to improvements in cognition.
Twenty-six patients with chronic schizophrenia were randomized to either 48 hours (over 16 weeks) of a drill-and-practice working memory-focused REM or an active placebo condition. All participants underwent cognitive assessment (MATRICS Consensus Cognitive Battery), as well as both resting and task-based fMRI before and after their respective intervention. All clinicians, technicians, and raters were blind to participant condition.
We observed changes in resting-state connectivity in the PFC for the REM group but not the placebo group. Increased intrinsic connectivity between the thalamus and right middle frontal gyrus correlated with improvements in overall cognition. Additionally, lower baseline cognition correlated with greater increases in connectivity between the thalamus and PFC. Similar findings were observed when patients were scanned during a working memory task.
These results suggest that increases in thalamo-prefrontal circuitry correspond with training-related improvements of the cognitive deficits associated with schizophrenia.
丘脑投射至前额叶皮质（PFC）对认知至关重要，这些神经回路的破坏被认为是精神分裂症病理生理学的基础。认知康复训练（REM）是一种行为干预措施，有望改善精神分裂症患者的认知和功能，但尚未研究其对丘脑 - 前额叶连接的影响程度。本研究旨在确定接受REM安慰剂对照试验的精神分裂症患者丘脑与PFC之间的功能连接是否增加，以及这些变化是否与认知改善相对应。
26例慢性精神分裂症患者被随机分为两组，一组接受为期48小时（共16周）以训练和练习工作记忆为主的REM训练，另一组接受活性安慰剂治疗。所有参与者在各自干预前后均接受认知评估（MATRICS共识认知成套测验）以及静息态和基于任务的功能磁共振成像检查。所有临床医生、技术人员和评估人员均对参与者的分组情况不知情。
我们观察到REM组而非安慰剂组前额叶皮质静息态连接的变化。丘脑与右侧额中回之间内在连接的增加与整体认知的改善相关。此外，较低的基线认知水平与丘脑和PFC之间连接性的更大增加相关。在工作记忆任务期间对患者进行扫描时也观察到了类似的结果。
这些结果表明，丘脑 - 前额叶神经回路的增加与精神分裂症相关认知缺陷的训练相关改善相对应。
