Matsui Mie, Suzuki Michio, Zhou Shi-Yu, Takahashi Tsutomu, Kawasaki Yasuhiro, Yuuki Hiromi, Kato Kanade, Kurachi Masayoshi
Department of Neuropsychology, Graduate School of Medicine, University of Toyama, Toyama, Japan.
Prog Neuropsychopharmacol Biol Psychiatry. 2008 Dec 12;32(8):1854-62. doi: 10.1016/j.pnpbp.2008.08.018. Epub 2008 Sep 5.
The present study investigated the relationship between memory strategy use and prefrontal gray/white matter volumes of healthy control subjects, patients with schizophrenia or schizotypal disorder. Gray/white matter volumes were measured for the superior, middle, inferior, ventral medial and orbital prefrontal regions, using high-resolution magnetic resonance (MR) images that were acquired from 35 patients with schizophrenia, 25 patients with schizotypal disorder and 19 healthy subjects. Participants were also administered the Japanese Verbal Learning Test (JVLT). In control subjects, larger left inferior frontal and straight gyrus's gray matter volumes were associated with higher semantic clustering rates on the JVLT, and smaller left inferior frontal gray matter volumes were associated with higher serial clustering ratio. In schizophrenic patients, smaller left orbitofrontal gray matter volumes were associated with lower semantic clustering rates on the JVLT. In schizotypal patients, smaller left inferior frontal white matter volume was associated with smaller serial clustering rates and larger semantic clustering rate. These findings suggest that semantic organization in schizophrenic patients might depend on mobilization of a memory strategy that is mediated by orbitofrontal cortex functioning. Failure to use a semantic organization strategy might be related to reduced volume in the inferior frontal gyrus. The findings for schizotypal patients suggest a compensation mechanism to remember the words using a serial processing strategy is at work when the inferior frontal gyrus cannot mediate semantic processing.
本研究调查了健康对照者、精神分裂症患者或分裂型障碍患者的记忆策略使用与前额叶灰质/白质体积之间的关系。使用从35例精神分裂症患者、25例分裂型障碍患者和19名健康受试者获取的高分辨率磁共振（MR）图像，测量了前额叶上、中、下、腹内侧和眶部区域的灰质/白质体积。参与者还接受了日本言语学习测试（JVLT）。在对照者中，左侧额下回和直回较大的灰质体积与JVLT上较高的语义聚类率相关，而左侧额下回较小的灰质体积与较高的序列聚类率相关。在精神分裂症患者中，左侧眶额灰质体积较小与JVLT上较低的语义聚类率相关。在分裂型障碍患者中，左侧额下回较小的白质体积与较小的序列聚类率和较大的语义聚类率相关。这些发现表明，精神分裂症患者的语义组织可能依赖于由眶额皮质功能介导的记忆策略的调动。未能使用语义组织策略可能与额下回体积减小有关。分裂型障碍患者的研究结果表明，当下额回不能介导语义加工时，一种使用序列加工策略来记忆单词的补偿机制在起作用。
