Berl M M, Balsamo L M, Xu B, Moore E N, Weinstein S L, Conry J A, Pearl P L, Sachs B C, Grandin C B, Frattali C, Ritter F J, Sato S, Theodore W H, Gaillard W D
Department of Neurosciences, Children's National Medical Center, George Washington University School of Medicine, Washington, DC, USA.
Neurology. 2005 Nov 22;65(10):1604-11. doi: 10.1212/01.wnl.0000184502.06647.28.
To investigate the degree of language dominance in patients with left and right hemisphere seizure foci compared to normal volunteers using a fMRI reading comprehension task.
Fifty patients with complex partial epilepsy, aged 8 to 56 years and 33 normal volunteers, aged 7 to 34 had fMRI (1.5 T) and neuropsychological testing. Participants silently named an object described by a sentence compared to a visual control. Data were analyzed with region of interest (ROI) analysis based on t maps for inferior frontal gyrus (IFG), midfrontal gyrus (MFG), and Wernicke area (WA). Regional asymmetry indices (AIs) were calculated [(L - R)/(L + R)]; AI > 0.20 was deemed left dominant and AI < 0.20 as atypical language.
Left hemisphere focus patients had a higher likelihood of atypical language than right hemisphere focus patients (21% vs 0%, chi2 < 0.002). Left hemisphere focus patients, excluding those with atypical language, had lower regional AI in IFG, MFG, and WA than controls. Right hemisphere focus patients were all left language dominant and had a lower AI than controls in WA and MFG, but not for IFG. AI in MFG and WA were similar between left hemisphere focus/left language patients and right hemisphere focus patients. Patients activated more voxels than healthy volunteers. Lower AIs were attributable to greater activation in right homologous regions. Less activation in the right-side WA correlated with better verbal memory performance in right focus/left hemisphere-dominant patients, whereas less strongly lateralized activation in IFG correlated better with Verbal IQ in left focus/left hemisphere-dominant patients.
Patients had lower asymmetry indices than healthy controls, reflecting increased recruitment of homologous right hemisphere areas for language processing. Greater right hemisphere activation may reflect greater cognitive effort in patient populations, the effect of epilepsy, or its treatment. Regional activation patterns reflect adaptive efforts at recruiting more widespread language processing networks that are differentially affected based on hemisphere of seizure focus.
使用功能磁共振成像（fMRI）阅读理解任务，调查与正常志愿者相比，左右半球癫痫病灶患者的语言优势程度。
50名年龄在8至56岁的复杂部分性癫痫患者和33名年龄在7至34岁的正常志愿者接受了fMRI（1.5T）和神经心理学测试。参与者默读一个句子描述的物体，并与视觉对照进行比较。基于额下回（IFG）、额中回（MFG）和韦尼克区（WA）的t图，采用感兴趣区（ROI）分析对数据进行分析。计算区域不对称指数（AI）[（L - R）/（L + R）]；AI > 0.20被视为左侧优势，AI < 0.20被视为非典型语言。
左半球病灶患者出现非典型语言的可能性高于右半球病灶患者（21%对0%，卡方检验< 0.002）。排除非典型语言患者后，左半球病灶患者在IFG、MFG和WA的区域AI低于对照组。右半球病灶患者均为左侧语言优势，在WA和MFG的AI低于对照组，但在IFG则不然。左半球病灶/左侧语言患者与右半球病灶患者在MFG和WA的AI相似。患者比健康志愿者激活了更多体素。较低的AI归因于右侧同源区域的更大激活。右侧WA激活较少与右病灶/左侧半球优势患者更好的言语记忆表现相关，而IFG激活的较少强烈偏侧化与左病灶/左侧半球优势患者更好的言语智商相关。
患者的不对称指数低于健康对照组，这反映了在语言处理过程中右侧同源区域的招募增加。右侧半球更大的激活可能反映了患者群体中更大的认知努力、癫痫的影响或其治疗效果。区域激活模式反映了在招募更广泛的语言处理网络方面的适应性努力，这些网络会因癫痫病灶所在半球的不同而受到不同影响。
