Holcomb H H, Medoff D R, Caudill P J, Zhao Z, Lahti A C, Dannals R F, Tamminga C A
Maryland Psychiatric Research Center, Johns Hopkins Medical Institutes, Baltimore 21228-0247, USA.
Cereb Cortex. 1998 Sep;8(6):534-42. doi: 10.1093/cercor/8.6.534.
Tone recognition is partially subserved by neural activity in the right frontal and primary auditory cortices. First we determined the brain areas associated with tone perception and recognition. This study then examined how regional cerebral blood flow (rCBF) in these and other brain regions correlates with the behavioral characteristics of a difficult tone recognition task. rCBF changes were assessed using H2(15)O positron emission tomography. Subtraction procedures were used to localize significant change regions and correlational analyses were applied to determine how response times (RT) predicted rCBF patterns. Twelve trained normal volunteers were studied in three conditions: REST, sensory motor control (SMC) and decision (DEC). The SMC-REST contrast revealed bilateral activation of primary auditory cortices, cerebellum and bilateral inferior frontal gyri. DEC-SMC produced significant clusters in the right middle and inferior frontal gyri, insula and claustrum; the anterior cingulate gyrus and supplementary motor area; the left insula/claustrum; and the left cerebellum. Correlational analyses, RT versus rCBF from DEC scans, showed a positive correlation in right inferior and middle frontal cortex; rCBF in bilateral auditory cortices and cerebellum exhibited significant negative correlations with RT These changes suggest that neural activity in the right frontal, superior temporal and cerebellar regions shifts back and forth in magnitude depending on whether tone recognition RT is relatively fast or slow, during a difficult, accurate assessment.
音调识别部分由右侧额叶和初级听觉皮层的神经活动所支持。首先，我们确定了与音调感知和识别相关的脑区。这项研究随后考察了这些脑区以及其他脑区的局部脑血流量（rCBF）如何与一项困难的音调识别任务的行为特征相关。使用H2(15)O正电子发射断层扫描评估rCBF的变化。采用减法程序定位显著变化区域，并应用相关分析来确定反应时间（RT）如何预测rCBF模式。对12名经过训练的正常志愿者在三种条件下进行了研究：静息（REST）、感觉运动控制（SMC）和决策（DEC）。SMC-REST对比显示初级听觉皮层、小脑和双侧额下回的双侧激活。DEC-SMC在右侧额中回和额下回、岛叶和屏状核；前扣带回和辅助运动区；左侧岛叶/屏状核；以及左侧小脑中产生了显著的簇。相关分析，即DEC扫描的RT与rCBF的相关性分析，显示在右侧额下和额中皮层呈正相关；双侧听觉皮层和小脑的rCBF与RT呈显著负相关。这些变化表明，在一项困难、准确的评估过程中，右侧额叶、颞上叶和小脑区域的神经活动幅度会根据音调识别RT相对较快还是较慢而来回变化。
