Left and right basal ganglia and frontal activity during language generation:: Contributions to lexical, semantic, and phonological processes
Left and right basal ganglia and frontal activity during language generation:: Contributions to lexical, semantic, and phonological processes
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DOI：
10.1017/s135561770397010x
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发表时间：
2003-11-01
影响因子：
2.6
通讯作者：
Briggs, RW
中科院分区：
文献类型：
--
作者：
Crosson, B;Benefield, H;Briggs, RW
功能磁共振成像被用来确定额叶，基底神经节，丘脑结构从事的三个方面的语言生成：词汇状态的生成项目，使用语义与语音信息在语言生成过程中，和生成速度。在功能磁共振成像中，21名神经正常的受试者执行了四项任务：产生无意义音节的开头和结尾辅音混合，产生单词的押韵单词，以快速的速度产生单词的语义类别（与无意义音节产生的速度相匹配），以及以慢速产生单词的语义类别（与押韵单词的产生速度相匹配）。左前SMA背侧尾状核腹侧丘脑前环的组件是活跃的，在词生成过程中从押韵或类别线索，但不是在无意义的音节生成。研究结果表明，这个循环是参与检索单词从预先存在的词汇存储。相对弥漫性活动在右侧基底神经节（尾状核和壳核）也被发现在字生成任务，但在无意义音节生成。鉴于相对缺乏的右额叶活动在单词生成任务，我们认为，右基底神经节活动抑制右额叶活动，防止右额叶结构干扰语言生产。目前的研究结果确立了左右基底神经节在单词生成中的作用。假设进行了讨论，为今后的研究，以帮助我们完善基底神经节功能的理解语言生成。
fMRI was used to determine the frontal, basal ganglia, and thalamic structures engaged by three facets of language generation: lexical status of generated items, the use of semantic vs. phonological information during language generation, and rate of generation. During fMRI, 21 neurologically normal subjects performed four tasks: generation of nonsense syllables given beginning and ending consonant blends, generation of words given a rhyming word, generation of words given a semantic category at a fast rate (matched to the rate of nonsense syllable generation), and generation of words given a semantic category at a slow rate (matched to the rate of generating of rhyming words). Components of a left pre-SMA-dorsal caudate nucleus-ventral anterior thalamic loop were active during word generation from rhyming or category cues but not during nonsense syllable generation. Findings indicate that this loop is involved in retrieving words from pre-existing lexical stores. Relatively diffuse activity in the right basal ganglia (caudate nucleus and putamen) also was found during word-generation tasks but not during nonsense syllable generation. Given the relative absence of right frontal activity during the word generation tasks, we suggest that the right basal ganglia activity serves to suppress right frontal activity, preventing right frontal structures from interfering with language production. Current findings establish roles for the left and the right basal ganglia in word generation. Hypotheses are discussed for future research to help refine our understanding of basal ganglia functions in language generation.