Clinical Neurology and Neurosurgery 101 (1999) 29 – 32 Case report Supplementary motor area aphasia: a case report Ming-Chyi Pai * Di6ision of Beha6ioral Neurology, Department of Neurology, National Cheng Kung Uni6ersity Hospital, 138 Shen Li Road, Tainan 704, Taiwan, ROC Received 25 May 1998; received in revised form 1 September 1998; accepted 20 October 1998 Abstract A 72-year-old right-handed woman developed aphasia after a left supplementary motor area (SMA) infarct. She had a right hemiparesis, more paretic on the leg, a tendency to look to her left, and loss of spontaneity. Neuropsychological deficits were mainly in the initiation of language production. She did not speak spontaneously, but responded and articulated well to questions. She named objects correctly when presented, and could repeat words, phrases, and sentences well. She had a difficulty in reading aloud, writing spontaneously and writing to dictation, but preserved the ability to copy written material. This is another rare case of SMA aphasia. © 1999 Elsevier Science B.V. All rights reserved. Keywords: Aphasia; Language; Speech initiation; Stroke; Supplementary motor area 1. Introduction Lichtheim [1] has described a variant of motor aphasia, characterized by speech and writing, similar to those of Broca’s aphasia, but with preserved repetition, writing to dictation, and reading aloud, which is now called transcortical motor aphasia (TMA). The loci of the lesion causing TMA include white matter anterolateral to the left frontal horn and the mesial frontal lobe involving the left supplementary motor area (SMA) [2,3]. Later, several cases with a peculiar aphasia syndrome after a lesion confined to the left SMA had been reported, which was characterized by a lack of spontaneous initiation of speech, although speech, when produced, is well articulated [4,5]. Although originally considered a subtype of TMA, SMA aphasia has been recognized as an independent syndrome [6]. Here, I report a lady with a left SMA infarct whose deficit was mainly in the initiation of language produc* Tel.: +886-6-2353535; fax: + 886-6-2088036. E-mail address: pair@mail.ncku.edu.tw (M.-C. Pai) tion, and her cerebral single photon emission computed tomography (SPECT) study revealed a more extensive involvement. 2. Case report 2.1. Clinical course A 72-year-old right-handed woman was first observed crawling on the ground, and having weakness of the right extremities and difficulty in speech in the morning of 14 March 1996. On arrival, her blood pressure was 127/92 mmHg, pulse 107, irregular. She appeared alert, but behaved less active and silent. She understood and followed simple verbal commands, but responded slowly and often said ‘yes’ or ‘no’ in English. On a confrontation object naming test, she said ‘pencil’, ‘book’, and ‘key’ in English instead of her mother tongue, Taiwanese. The visual fields were intact, but she had a tendency to look to the left. She had right hemiparesis, more paretic on the leg, but no sphincter 0303-8467/99/$ - see front matter © 1999 Elsevier Science B.V. All rights reserved. PII: S 0 3 0 3 - 8 4 6 7 ( 9 8 ) 0 0 0 6 8 - 7 30 M.-C. Pai / Clinical Neurology and Neurosurgery 101 (1999) 29–32 incontinence. The remainder of the neurological examination was unremarkable. Electrocardiography showed atrial fibrillation. Her past medical history included atrial fibrillation and poorly controlled hypertension for more than 10 years. She was transferred to a rehabilitation facility on the 13th day and was discharged on the 43rd day, when she still had difficulty in the initiation of speech, and frequently halted in conversation. 2.2. Neuropsychological assessment Neuropsychological assessment was carried out from her eighth to 12th postattack day (PAD), when she was stable and cooperative. The patient has a junior high school education and could speak Taiwanese, Mandarin, and Japanese. She could also speak English because she had worked as a housekeeper for Americans for 1 year. The digit span was seven forward and three backward. She scored eight points out of 10 in a short portable mental status questionnaire [7], in which she failed in the items of date and calculation. She showed neither hemineglect, by bisection and cancellation tasks [8], nor perseveration or omission on continuing alternating sequences by visual pattern completion. She successfully performed Part A of the Trail Making Test, but performed badly on Part B. She recalled three out of three objects after 5 min and the remote memory appeared intact. She carried out daily activities as usual but slower, and showed neither alien hand sign nor apraxia. Regarding the language function, the patient did not initiate conversation, but remained silent until spoken to. On request, she described her occupational experiences and how she was sent to the hospital, with hesitation, struggle, and frequent pauses. However, the key events, persons, and time sequences were correct. She repeated single words, phrases and sentences accurately with good articulation. She named eight out of eight real objects (pencil, comb, scissors, spoon, toothbrush, key, button, and match), although in English for pencil, key and match, and in Japanese for comb on the first occasion, which she named in Taiwanese on request. When names of the objects were given, she could point to four in requested orders. She gave her name and address correctly, but wrote them with paragraphia. She failed in writing to dictation of 16 two-syllable words, but read aloud 10 of them, and copied all of them stroke by stroke. She read only initial parts of long sentences; the remainders were either read in disordered sequence or in a paraphasic pattern. Verbal comprehension appeared normal. In summary, this patient had deficits mainly in the initiation of language pro- duction (Table 1), without affecting general intelligence and memory. 2.3. Diagnostic imaging On her first PAD, the findings on a brain computed tomography were consistent with an infarct in the territory of the left anterior cerebral artery, compromising the middle mesial frontal region. Cerebral magnetic resonance imaging on the 14th PAD showed a left mesial frontal cortical lesion with enhancement (Fig. 1), compatible with the location of the SMA and anterior cingulate gyrus. These areas were consistent with the territory supplied by the middle and posterior internal frontal branches of the callosomarginal artery [9]. A cerebral Tc-99m HMPAO SPECT study performed on her eighth PAD showed hyperperfusion in the left mesial frontal area. A second SPECT on the 24th PAD showed no uptake at the left anterior frontal area and hypoperfusion in the left parietal-temporal area. 3. Discussion Aphasia results from a breakdown of the two-way translation that establishes a correspondence between thoughts and language [10]. The aphasics cannot accurately convert the sequences of non-verbal mental representations that constitute thought into the symbols and grammatical organization that constitutes language [10]. Written code of language may also be compromised. Accordingly, this patient had a true aphasia since she had writing and reading disturbances in addition to the speech difficulty. Regarding her aphasia and the well-defined lesion, this patient is similar to the patient described by Masdeu et al. [4] (Table 2). Among the differences are that this patient had no initial mutism, and preserved ability to copy Table 1 Language assessment Items Results Spontaneous speech Response to queries Repetition Naming Verbal comprehension Writing Copying Dictation Reading No Hesitation, effortful, frequent pauses, correct context Good for single words, phrases and sentences 8/8 real objects Good Paragraphia 16/16 words* 0/16 words 10/16 words, but failed in sentences * Stroke by stroke. M.-C. Pai / Clinical Neurology and Neurosurgery 101 (1999) 29–32 Fig. 1. Sagittal (A) and coronal (B) T1-weighted magnetic resonance imaging (TR, 570 ms; TE, 15 ms) showing a lesion with gadolinium enhancement at the left mesial frontal region, compatible with supplementary motor area. while being poor in reading aloud. However, it is difficult to determine whether the copying of the written material as well as the repetition of the spoken language was performed via semantic or phonological pathways, because her language output was so impaired. In addition, it is quite different from the maniTable 2 Comparison of the aphasia syndrome Items TMAa Masdeu’sb This case Initial mutism Spontaneous speech Articulation Writing Dictation Copying Repetition Verbal comprehension Object naming Reading aloud Echolalia Yes Poor Poor Poor Good ? Good Good Poor Good Yes Yes Poor Good Poor Poor ? Good Good Good Good No No Poor Good Poor Poor Good Good Good Good Poor No a b TMA, transcortical motor aphasia. Masdeu’s patient with left supplementary motor area damage [4]. 31 festations of patients with TMA (Table 2). Another peculiar finding is her pattern of copying, namely stroke by stroke. It was most likely caused by slow motion instead of by apractic agraphia, as one might think of. Apractic agraphia is impairment in writing in which the actual orthographic production of letters and words is abnormal, despite normal sensorimotor function, visual feedback, and word and letter knowledge [11]. Apractic agraphia is usually caused by a parietal lesion of the hemisphere dominant for language. Botez and Barbeau [12] proposed two speech systems in parallel. The elementary system, a phylogenetically older system, is responsible for speech initiation, speech fluency and volume, and control of articulation and speech motor planning. It consists of the periaqueductal gray matter, the ventrolateral thalamic area, the anterior cingulate gyrus, Broca’s area, and portions of the corticostriatal system [12]. The other is the conceptual system, including the pulvinar nucleus, nucleus lateralis posterior of the thalamus, and posterior cortical language areas [12]. It is responsible for the interpretation and manipulation of the external and internal symbol systems, including phonological, semantic, and syntactic aspects of language [12]. Destruction of the fibers from the SMA to the lateral premotor cortex may disconnect the limbic ‘starter mechanism’ of speech from the cortical region that control motor speech [12]. This may result in mutism, usually followed by impaired initiation, prolonged response latency and disturbed fluency [3]. The SMA has thus been viewed as the most cephalad portion of an integrated brain mechanism responsible for the initiation of speech [12]. For this patient, the responsible lesion involved the left SMA and anterior cingulate gyrus, between which there are reciprocal connections [13]. This is further supported by a study of 26 patients with mesial frontal lesions, showing that the mutism is a common symptom after left SMA damage [14]. Recently, and most characteristically, Ackermann et al. [15] reported a woman with left SMA damage having ictal epileptic vocalizations in terms of involuntary repetition trains of the syllable /da/. Finally, the symptoms of a patient with a cerebral infarct will reflect the loss of function in the territory of the affected vessels. However, using positron emission tomography, Kuhl et al. [16] have shown disturbance of cerebral function at sites remote from an ischemic area, a phenomenon known as diaschisis [17,18]. Judging from the SPECT findings of hypoperfusion in the left parietal-temporal area and no uptake in the left SMA, it is possible that this patient had a more extensive cortical dysfunction, possibly via the mechanism of diaschisis. This might explain in part why this patient was poor in reading aloud as well as in writing to dictation. 32 M.-C. Pai / Clinical Neurology and Neurosurgery 101 (1999) 29–32 Acknowledgements This study was in part supported by a grant from Department of Health, ROC (DOH-87-HR-707). 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