Western Aphasia Battery Scores Research Articles

Diagnosis of Aphasia from Electroencephalogram Using Neural Network

Diagnosis of aphasia from electroencephalogram (EEG) was investigated. EEG data of the following patients were collected; the patient of total aphasia who is difficult to understand the speech and the patient of motor aphasia (Broca aphasia) who feels pain or makes some grammatical mistakes when he speaks anything while he can understand the speech. At first, power spectrum of EEG was extracted by the fast Fourier transform (FFT). The spectrum was separated into 9 regions, corresponding to the characterized wave. The regions with 4.0 to 5.9, 6.0 to 7.9 and 8.0 to 12.9 Hz were selected as the frequency band of θ1, θ2, and α waves, respectively. Assessment of linguistic ability was carried out by Western aphasia battery (WAB). The relative power values were input into each NN model for estimation of aphasia quotient (AQ) score or score on spontaneous speech from WAB. In NN model for AQ score, 7 input valuables were selected by PIM; θ1 values of channel 2,3, and 11, θ2 values of channel 4, 9, and 13, and α value of channel 11. The average error of this model was 8.6 points, corresponding to the relative error of 10%. It was found that the model can estimate the AQ value at high accuracy. Another NN model to estimate the score on spontaneous speech was also constructed. The average error of this model with actual WAB score was 1.8 points. Predicted score of patient with motor aphasia coincided well with the actual score.

Effects of resective surgery for left-sided intracranial tumours on language function: a prospective study

Although language disorders occur in about 50% of patients with a left hemispheric tumour and are a significant cause of morbidity, the effects of resective neurosurgery and their relation to tumour pathology are unclear. We report the immediate effects of resective surgery on language functions in a heterogeneous group of patients with left-sided intracranial tumours. 40 patients were studied. The Western Aphasia Battery (WAB) and Boston Naming Test (BNT) were administered preoperatively and before discharge following resective neurosurgery. Dexamethasone dose at time of testing was recorded, as was time taken to complete the tests, and tumour neuropathology. 15 patients with normal aphasia quotients and language quotients before resective surgery all had normal quotients postoperatively. 25 who were dysphasic (ie, aphasia quotient <93.8) preoperatively showed significant postoperative improvements in both their mean aphasia quotient (from 81.8 to 89.1, p=0.004) and their mean language quotient (from 73.4 to 85.4, p=0.001), though 13 remained dysphasic. Two of the 25 dysphasic patients had their WAB scores lowered by tumour resection. The findings and postoperative changes in BNT scores were almost identical to the pattern of those in WAB scores. At second assessment, dexamethasone therapy was significantly (p<0.01) lower than preoperative dose (reduction from mean 10.3 mg/day to 0.7 mg/day in the dysphasic group). Patients with glioblastoma were more likely to have lower aphasia quotients, language quotients, and BNT scores than patients with anaplastic glioma, metastasis, or meningioma. Although the glioblastoma group had the greatest improvements in WAB operative scores, 57% remained dysphasic after resective surgery. Two additional patients declined postoperative assessment. Resective surgery for left-sided intracranial tumours significantly improves language function in dysphasic patients, and is unlikely to impair language functions in non-dysphasic patients. Dysphasia and its response to resective surgery are related to the tumour neuropathology.

Assessment of communication impairment and the effects of resective surgery in solitary, right-sided supratentorial intracranial tumours: a prospective study

To assess the effects of solitary, right-sided supratentorial intracranial tumours on language and communication function patients were assessed preoperatively using the Western Aphasia Battery (WAB) and Boston Naming Test (BNT). The impact of resective tumour surgery was evaluated prospectively by a comparison of test scores obtained at pre- and postoperative assessments. The WAB scores in 33 patients revealed that 21% were by definition dysphasic (i.e. Aphasia Quotient 93.8) and 35% obtained an abnormal Language Quotient. Performance was particularly variable on the written picture description and word fluency WAB subtests. Using the BNT 21% of 47 patients were anomic. The tumours were evenly distributed throughout the frontal, temporal and parietal lobes, but none were in the occipital lobe. Reassessment approximately 6 days after excisional tumour surgery showed that mean scores for the BNT, Aphasia Quotient, and the WAB spontaneous speech and comprehension subtests had improved significantly despite a significant reduction in dexamethasone therapy. This study has demonstrated that right-sided intracranial tumours produce subtle, but specific language deficits of a type more usually associated with left-sided brain dysfunction. The pathophysiological basis of these deficits is unclear, but they are not attributable to either limited education or pre-existing dyslexia. Further studies using a discriminating and comprehensive assessment of language in the right hemisphere are required.

Stereotactic biopsy of nonpolar tumors in the dominant hemisphere: a prospective study of effects on language functions.

A prospective study of patients undergoing computerized tomography (CT)-guided stereotactic biopsy of nonpolar tumors in the dominant hemisphere was undertaken to determine if stereotactic biopsy caused a deterioration of language functions. Language was assessed using the Western Aphasia Battery (WAB) and the Boston Naming Test (BNT) before and after a biopsy sample was obtained. Of 16 patients studied, five (31%) were dysphasic preoperatively. After the biopsy the Aphasia Quotient (AQ), derived from the WAB, had significantly deteriorated in four (80%) of these patients, whereas in the fifth it remained relatively unchanged. One of these patients with an extensive infiltrating hemispheric oligoastrocytoma subsequently recovered normal language function after radiotherapy. In 10 of the 11 patients who had normal language function preoperatively there were no deleterious changes after biopsy in either the WAB subtest or BNT scores. In the other patient whose WAB score was normal preoperatively, there was a significant deterioration in postoperative AQ. This patient, who declined steroid therapy before and after biopsy, had a glioblastoma multiforme in Wernicke's area. A postoperative CT scan revealed no changes from what was shown on preoperative scan. This clinical study shows that CT-guided stereotactic biopsy of nonpolar tumors in the dominant hemisphere using the Brown-Roberts-Wells system and the Sedan-Nashold biopsy cannula carries a 9% risk (95% confidence intervals 0-26%) of impairing language functions if the patient is not dysphasic preoperatively. If the patient is dysphasic preoperatively, there is a very high risk of aggravating the dysphasia with stereotactic biopsy.

Temporoparietal Cortex in Aphasia

Forty-four aphasic patients were examined with (F18)-fluorodeoxyglucose positron emission tomography in a resting state to determine whether consistent glucose metabolic abnormalities were present. Ninety-seven percent of subjects showed metabolic abnormalities in the angular gyrus, 89% in the supramarginal gyrus, and 87% in the lateral and transverse superior temporal gyrus. Pearson product moment correlations were calculated between regional metabolic measures and performance on the Western Aphasia Battery. No significant correlations were found between the Western Aphasia Battery scores and right hemisphere metabolic measures. Most left hemisphere regions correlated with more than one score from the Western Aphasia Battery. Temporal but not frontal regions had significant correlations to the comprehension score. The left temporoparietal region was consistently affected in these subjects, suggesting that common features in the aphasias were caused by left temporoparietal dysfunction, while behavioral differences resulted from (1) the extent of temporoparietal changes, and (2) dysfunction elsewhere in the brain, particularly the left frontal and subcortical areas.

Intelligence and aphasia: Performance of aphasics on Raven's coloured progressive matrices (RCPM)

The usual verbal tests of intelligence are inappropriate in aphasia. Nonverbal intelligence was measured by Raven's test (RCPM) in 111 aphasics and 52 controls, whose language function was scored by the Western Aphasia Battery (WAB). The patients were classified according to taxonomic criteria, based on the WAB scores. The results indicate that Global, Wernicke's, and Transcortical Sensory aphasics perform poorly on the RCPM. Common to all these is poor comprehension. Broca's Transcortical Motor, Conduction, and Anomic aphasics do as well as nonaphasic controls with diffuse brain damage or nondominant hemisphere lesions. The RCPM performance does not seem to be related directly to the severity of aphasia. In addition to comprehension, drawing scores appeared to correlate best with RCPM scores. The data suggest that “nonverbal” intelligence is also imparied in aphasics to a variable extent, but 42% of aphasics performed as well as the controls without brain damage on RCPM.