RECOVERY FROM UNILATERAL VISUO-SPATIAL NEGLECT? 1 D. C. Campbell and

J.

M. Oxbury

(Oxford University, Department of Clinical Neurology)

INTRODUCTION

In a previous report Oxbury, Campbell and Oxbury (1974) described defects of spatial analysis and visual perception in a group of patients 3-4 weeks after a right hemisphere stroke. The defects occurred predominantly, although not solely, amongst the patients with left visuo-spatial neglect, defined by failure to complete the left side of one or more of four drawings. This disability could not be attributed to general intellectual deterioration. Attention was drawn to the association of left neglect and poor performance on visuo-spatial tests, but no definite evidence for a causal relationship could be adduced. Little is known about changes in visuo-spatial neglect in relation to time since the onset. Battersby, Bender, Pollack and Kahn (1956) demonstrated a positive relationship between manifestations of neglect and a fluctuating clinical course in some terminal tumour patients. Lawson ( 1962) discussed two cases of left visuo-spatial neglect and described some improvement in reading and drawing with training over different periods extending up to 2 years in one patient. Gainotti ( 1968) claimed that neglect is overwhelmingly manifest in the early stages after the cerebral incident and reported complete recovery by 3 years. In contrast, Zarit and Kahn ( 1974) found evidence of inattention up to 12 years after onset. In the present study a group of patients was examined 3-4 weeks and 6 months after a stroke. The changes in measures of left visuo-spatial neglect and in performance on visuo-spatial and perceptual tasks are reported. The results may throw some light on the relationship between neglect and other visuo-spatial disturbances.

1

This work was supported by The Medical Research Council: Grant No. G972/117C.

Cortex (1976) 12, 303-312.

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D. C. Campbell and ]. M. Oxbury MATERIAL AND METHOD

Subjects

All patients had been admitted to either the Churchill Hospital or the Radcliffe Infirmary because of a stroke and were selected from a group of over 250 patients seen by the Neurology Department's Stroke Service between December 1971 and September 1973. The criteria for selection were that they were aged less than 65 years and right-handed, that English was their native language and that they had suffered a right hemisphere stroke without a previous history of cerebral pathology. All patients who fulfilled these criteria and who had been given a neuropsychological examination 3-4 weeks after the onset of the stroke and 5 months later were included in the study except 5 cases aged 18-22 years, who were excluded because they were very much younger than the other patients. Details of the neurological examination will be found in Oxbury et al. (1974). Whether or not a patient was considered to show evidence of unilateral visuo-spatial neglect depended on his performance on a copying and drawing task discussed below. This criterion identified 2 sub-groups of right hemisphere patients, as described by Oxbury et al. ( 197 4 ). Two patients who died and one who suffered a further stroke before reassessment are excluded from this analysis. The 2 sub-groups have the following characteristics: (a) right hemisphere neglect positive sub-group (RN + ): 6 patients, average age 58.66 years, range 53-63 years. (b) right hemisphere neglect negative sub-group (RN- ): 8 patients, average age 58.87 years, range 53-64 years. The ages of the sub-groups are not significantly different.. Procedure Neuropsychological examination

The following tests were administered between 3-4 weeks and again at 6 months after the stroke. The same test material was used on both occasions except where indicated. Tests of neglect Copying and Drawing. Whether or not a patient was considered to show evidence of unilateral visuo-spatial neglect depended upon his performance on a copying and drawing task. Each patient was required to copy a line drawing of a four-pointed star and of a cube, and to produce a free-hand drawing of a daisy and of a clock face with numbers. Those who failed to complete the left-hand side of any one of these four drawings were classified as showing neglect. Tests of spatial analysis and visual perception Block Design. The W AIS sub-test was administered in the standard fashion and an age-scaled score derived (Wechsler, 1958). Cube Counting. This task was taken directly from Ratcliff's modification of the cube analysis of the Stanford-Binet Intelligence Test (Ratcliff, 1970). Patients

Recovery from unilateral visuo-spatial neglect?

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were shown a series of 25 cards (15 X 10 em) each having a line drawing of a "pile" of cubes, the side of each measuring 1 em. They were required to count the number of cubes in the pile, including the hidden ones. Five practice cards were followed by the 20 test cards presented singly without time limit. Collin Incomplete Pictures. This test was originally devised by GoUin ( 1960) and its use with neurological patients as a test of visual perception has been described by Warrington and James ( 1967 ). The patients were presented with 10 sets of drawings. Each set consisted of 5 drawings of a common object. The first drawing was very incomplete; each successive drawing was progressively less incomplete until the fifth which was a full representation. The drawings in each set were presented one after the other from the most incomplete to complete, and the patient was asked to name the object as soon as he recognised it. The score for each set was the number of versions that had to be shown to achieve correct recognition. Thus the patient scored one point if he recognised the object from the most incomplete version and so on. If he failed to recognise the object even when shown the most complete version he was arbitrarily assigned 6 points. For the 10 sets the best possible score was 10 and the worst 60. Two parallel forms of the test were available. Visual Recognition. The stimuli used in this test were as in the "visual recognition test" of Warrington and James ( 196 7 ). On each trial the patient was shown a card with 5 black squares variously positioned in a 4 X 4 matrix: following a 5 second inspection period the card was removed and the patient as shown another card with 4 stimuli arranged in 2 columns of 2 side by side, one of which was identical to the stimulus shown during the inspection period. He had to indicate which this stimulus was. Twenty trials were given. On 10 trials the correct stimulus was in the right-hand column and on the other 10 it was in the left-hand column. Raven's Standard Progressive Matrices. The Standard Matrices were administered in the normal way (Raven, 1960). In the absence of any age difference between the groups and in the light of the limited norms available, raw scores were used in the statistical analysis. Tests of verbal cognitive abilities Personal Orientation. Nine questions were asked of the patient relating to age, date of birth, and orientation in time and place. Each correct response scored one point. Paragraph Recall. Each patient was read one or other of two paragraphs taken from the Wechsler Memory Scale Form I (Wechsler, 1945). Recall was tested immediately after presentation and after half-an-hour's delay. The score is the number of items correctly recalled at each time. The remaining paragraph was administered and scored in the same way at 6 months. Digit Span. Forward and backward spans were obtained following the standard WAIS administration, and an age-scaled score derived (Wechsler, 1958). Arithmetic. The WAIS arithmetic sub-test was administered in the standard fashion and an age-scaled score derived (Wechsler, 1958). Picture Naming. The pictures used were those prepared and described by Oldfield and Wingfield ( 1965 ). Thirty-six were presented, the first 10 being

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D. C. Campbell and ]. M. Oxbury

practice items. Each of the 26 test pictures were presented for a maximum of 10 seconds. Failure to respond within that time, or failure to produce the correct name at the first response, was scored as an error. Verbal Fluency: Open. The patient was asked to name as many objects as possible in 60 seconds. The score is the number of different object names produced within the time limit. Verbal Fluency: Closed. The patient was asked to name as many animals as possible in 60 seconds. The score is the number of different animal names produced within the time limit. RESULTS

The mean scores achieved by the sub-groups on each test on each assessment are given in T abies I and II. The scores were subjected to twoway analysis of variance with repeated measures on one factor.

Copying and drawing By definition, all six RN + patients showed neglect on one or more of the four drawings at three to four weeks post stroke. On reassessment, only two of these patients continued to demonstrate neglect. Examples of this group's drawings are shown in Figure 1.

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;'/'I 1

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b

Fig. 1 - Examples of drawings by the Neglect Group (RN + ). The top row shows examples of drawings by five neglect patients at three weeks: the bottom row, drawings by the same patients at six months, with only one (2nd from right) now being iudged to exhibit neglect.

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Recovery from unilateral visuo-spatial neglect?

Patients who had demonstrated unilateral visuo-spatial neglect on a simple drawing and copying task three to four weeks after a right hemisphere strok...
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