Department of Psychology, University of Konstanz, Konstanz, Germany.
PLoS One. 2012;7(7):e39051. doi: 10.1371/journal.pone.0039051. Epub 2012 Jul 18.
In a previous report we showed that cognitive training fostering auditory-verbal discrimination and working memory normalized magnetoencephalographic (MEG) M50 gating ratio in schizophrenia patients. The present analysis addressed whether training effects on M50 ratio and task performance are mediated by changes in brain oscillatory activity. Such evidence should improve understanding of the role of oscillatory activity in phenomena such as M50 ratio, the role of dysfunctional oscillatory activity in processing abnormalities in schizophrenia, and mechanisms of action of cognitive training.
METHODOLOGY/PRINCIPAL FINDINGS: Time-locked and non-time-locked oscillatory activity was measured together with M50 ratio in a paired-click design before and after a 4-week training of 36 patients randomly assigned to specific cognitive exercises (CE) or standard (comparison) cognitive training (CP). Patient data were compared to those of 15 healthy controls who participated in two MEG measurements 4 weeks apart without training. Training led to more time-locked gamma-band response and more non-time-locked alpha-band desynchronization, moreso after CE than after CP. Only after CE, increased alpha desynchronization was associated with normalized M50 ratio and with improved verbal memory performance. Thus, both types of cognitive training normalized gamma activity, associated with improved stimulus encoding. More targeted training of auditory-verbal discrimination and memory additionally normalized alpha desynchronization, associated with improved elaborative processing. The latter presumably contributes to improved auditory gating and cognitive function.
CONCLUSIONS/SIGNIFICANCE: Results suggest that dysfunctional interplay of ocillatory activity that may contribute to auditory processing disruption in schizophrenia can be modified by targeted training.
在之前的报告中，我们表明认知训练促进听觉言语辨别和工作记忆，使精神分裂症患者的脑磁图（MEG）M50 门控率正常化。本分析旨在探讨训练对 M50 比率和任务表现的影响是否通过脑振荡活动的变化来介导。这种证据应该可以提高对振荡活动在 M50 比率等现象中的作用的理解，对精神分裂症处理异常中功能失调的振荡活动的作用的理解，以及认知训练的作用机制的理解。
方法/主要发现：在一项配对点击设计中，我们在 36 名随机分配到特定认知练习（CE）或标准（对照）认知训练（CP）的患者进行为期 4 周的训练之前和之后，一起测量了与 M50 比率相关的时锁和非时锁振荡活动。将患者数据与 15 名健康对照者的数据进行比较，这些对照者在没有训练的情况下，在 4 周内进行了两次 MEG 测量。与 CP 相比，CE 后时锁γ波段反应和非时锁α波段去同步化增加更多。只有在 CE 后，增加的α去同步化与 M50 比率正常化和言语记忆表现改善相关。因此，两种类型的认知训练都使与刺激编码改善相关的γ活动正常化。对听觉言语辨别和记忆的更有针对性的训练还使与改善的精细加工处理相关的α去同步化正常化。后一种处理可能有助于改善听觉门控和认知功能。
结论/意义：结果表明，可能导致精神分裂症听觉处理中断的振荡活动的功能失调相互作用可以通过有针对性的训练来改变。
