School of Education, Bar-Ilan University Ramat-Gan, Israel ; Multidisciplinary Brain Research Center, Bar-Ilan University Ramat-Gan, Israel.
Tel Aviv-Brull Community Mental Health Center Tel Aviv, Israel.
Front Hum Neurosci. 2014 Oct 16;8:818. doi: 10.3389/fnhum.2014.00818. eCollection 2014.
Comprehension of conventional and novel metaphors involves traditional language-related cortical regions as well as non-language related regions. While semantic processing is crucial for understanding metaphors, it is not sufficient. Recently the precuneus has been identified as a region that mediates complex and highly integrated tasks, including retrieval of episodic memory and mental imagery. Although the understanding of non-literal language is relatively easy for healthy individuals, people with schizophrenia exhibit deficits in this domain. The present study aims to examine whether people with schizophrenia differentially recruit the precuneus, extending to the superior parietal (SP) cortex (SPL), to support their deficit in metaphor comprehension. We also examine interregional associations between the precuneus/SPL and language-related brain regions. Twelve people with schizophrenia and twelve healthy controls were scanned while silently reading literal word pairs, conventional metaphors, and novel metaphors. People with schizophrenia showed reduced comprehension of both conventional and novel metaphors. Analysis of functional connectivity found that the correlations between activation in the left precuneus/SPL and activation in the left posterior superior temporal sulcus (PSTS) were significant for both literal word pairs and novel metaphors, and significant correlations were found between activation in the right precuneus/SPL and activation in the right PSTS for the three types of semantic relations. These results were found in the schizophrenia group alone. Furthermore, relative to controls, people with schizophrenia demonstrated increased activation in the right precuneus/SPL. Our results may suggest that individuals with schizophrenia use mental imagery to support comprehension of both literal and metaphoric language. In particular, our findings indicate over-integration of language and non-language brain regions during more effortful processes of novel metaphor comprehension.
理解传统和新颖隐喻既涉及传统的语言相关皮质区域，也涉及非语言相关区域。虽然语义处理对于理解隐喻至关重要，但它并不足够。最近，顶内沟被确定为一个介导复杂和高度综合任务的区域，包括情节记忆和心理意象的检索。尽管健康个体相对容易理解非字面语言，但精神分裂症患者在这一领域存在缺陷。本研究旨在检验精神分裂症患者是否会以不同的方式招募顶内沟，延伸至顶上回（SP）皮层（SPL），以支持他们在隐喻理解方面的缺陷。我们还检查了顶内沟/SPL 与语言相关脑区之间的区域间关联。12 名精神分裂症患者和 12 名健康对照者在安静阅读字面词对、传统隐喻和新颖隐喻时接受了扫描。精神分裂症患者对传统隐喻和新颖隐喻的理解能力均下降。功能连接分析发现，左顶内沟/SPL 的激活与左后颞上沟（PSTS）的激活之间的相关性对于字面词对和新颖隐喻都是显著的，而在三种语义关系中，右顶内沟/SPL 的激活与右 PSTS 的激活之间存在显著相关性。这些结果仅在精神分裂症组中发现。此外，与对照组相比，精神分裂症患者的右顶内沟/SPL 激活增加。我们的结果可能表明，精神分裂症患者使用心理意象来支持对字面和隐喻语言的理解。特别是，我们的发现表明，在更费力的新颖隐喻理解过程中，语言和非语言脑区过度整合。
