对布洛卡氏失语症障碍的跨语言研究表明，患者对功能语类的理解和产出均有障碍。但并非所有功能语类受损程度相同。研究表明，CP及TP节点的功能语类易受损。对此，目前有几种解释，但是都主要基于屈折性语言，缺乏汉语这种非屈折性语言的证据，且对布洛卡氏失语症语言障碍的性质成因尚未达成共识。句法树剪裁假设认为是句法树上功能语类节点被截断，导致无法向高处节点投射。语迹删除假设认为是患者在运算句法移位过程中，语迹被删除，导致无法正常传递题元角色。T特征赋值不足假设认为并非是由于功能语类无法向高处投射，而是因为TP携带的T特征受损。可解读特征受损假设认为可解读特征比不可解读特征易受损。生成词序问题假设认为经过移位生成的句子更难。另有认知资源受限假说，认为患者在句子处理中认知资源受限，导致语言障碍。本研究由共时群组研究及历时个案研究两部分组成。共时研究有二十二名汉语为母语的布洛卡氏失语症患者及十名正常人参加。该研究观察受试自发性言语中功能语类的产出。结果表明，AspP/TP受损较轻，CP及vP受损严重，其中vP受损最重。结果还发现，患者的严重等级程度与功能语类节点之间的差距有关联。历时研究有一名汉语为母语的男性布洛卡氏失语症患者参加。该研究观察受试在四个月语言康复的过程中对功能语类的判断、理解及产出。结果表明，CP及vP比AspP/TP康复快，CP最先稳定下来，受损最重的vP一直处于康复活跃状态。两个研究结果合并显示，患者的AspP/TP 总体较好保留，vP受损最重，CP则现混合模式。现有的几种假设均不能完全解释及预测本文中来自汉语患者的研究结果。因此，本研究基于语段理论，提出一新假设。该假设认为，布洛卡氏失语症障碍的根本原因是在语段推导过程中，在最先进入运算的vP语段上出现问题，导致其后语段的相继运算低效问题，CP及TP功能语类出现的问题，仅仅是表象，所以才导致众说纷纭。本研究的创新价值及贡献有：1）汉语不同于其他西方语言，是非屈折性语言。对汉语布洛卡氏失语症患者的研究，补充了布洛卡氏失语症患者的功能语类障碍研究的不足。2）对母语为汉语的失语症实验研究，为汉语理论语言学提供了一个实践检测基地。3）从历时及共时角度对汉语功能语类障碍的总体研究，为失语症临床的语言评估及康复治疗提供了理论指导。

Cross-linguistic studies reveal that people with Broca's aphasia (PWBA) exhibit functional category deficits in both comprehension and production. However, not all the functional categories are equally impaired. It is largely evidenced that CP- and TP-related functional categories are more vulnerable. A number of hypotheses, linguistic or non-linguistic, have been formulated to account for these diverging deficit patterns. However, these hypotheses have dominantly focused on the inflected languages with inadequate evidence from other uninflected languages like Chinese. Until now there has been no consensus among researcher as to the nature of functional deficits in aphasia. Impaired hierarchy account ascribes the deficits to truncation of higher functional projections. Trace deleted account assumes that traces are impaired in derivation of movement. Feature specification account posits that tense features are underspecified without blocking of higher functional projection. Similar account further assumes that interpretable features are more impaired than uninterpretable features. Word order account emphasizes that derived order sentences are more impaired. Non-linguistic accounts capitalize on resource limitations of sentence processing. Against this background, this study seeks to investigate the relationship between accessibility of Chinese functional categories and degrees of severity of impairment, and relationship between the recovery process of Chinese PWBA and accessibility of functional categories. On the basis of the Chinese data, this study also dubs an alternative account. Additionally, this study sheds light on Chinese linguistics. Two studies were conducted in this dissertation. Twenty-two Chinese PWBA and ten NBD participated in the synchronic study. Their productions of functional categories are examined in spontaneous speech. Findings show that AspP/TP is better preserved whereas CP and vP are impaired, particularly vP is heavily impaired. It is found that degrees of severity of impairment are associated with the gap between the nodes. One Chinese agrammatics participated in the longitudinal study. His performance on functional categories in recovery process was tested across grammaticality judgment, comprehension, and production tasks. Findings show that CP and vP have been recovered faster than AspP/TP with vP most dynamic during recovery process. CP stabilizes first whereas AspP/TP is the slowest one. The two studies evidence that 1) AspP/TP in Chinese agrammatism is not badly impaired, 2) vP is heavily impaired, 3) CP manifests a mixed pattern. Additionally, this study reveals that generally comprehension and grammaticality judgment are better than production of functional categories. Also, for Chinese PWBA past time is better than future time. None of the extant hypotheses are totally amenable to the Chinese data in this study. Hence this study suggests an alternative account based on the phase theory. This account assumes that impaired vP underlie CP- and TP-related deficits. Besides, this study expounds some implications for Chinese linguistics. This study contributes to agrammatic studies by providing data from the uninflected Chinese language. Furthermore, this study sheds light on Chinese linguistics with agrammatic data. Last, this study provides implications for clinician's assessment and treatment of aphasia.