J7ournal of Neurology, Neurosurgery, and Psychiatry 1992;55:717-719 717 J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.55.8.717 on 1 August 1992. Downloaded from SHORT REPORT Left on the right: allochiria in a case of left visuo-spatial neglect Peter W Halligan. John C Marshall, Derick T Wade Abstract audition,8 and olfaction.9 The classic account A patient with left visuo-spatial neglect of visual (or optic) allochiria-where objects after right fronto-parietal haemorrhage located in one lateral hemispace are perceived failed to cross out stimuli in left space on in the opposite hemispace-was given by canceilation tests. Her bisections of hori- Herrmann and Poetzl.'0 Meador et al" pro- zontal lines were displaced significantly to vide historical analysis of some conceptual and the right of true centre. On drawing and terminological confusions in the area. copying tasks, she sometimes omitted fea- It is possible that neglect and allochiria are tures on the left (neglect) and sometimes theoretically-unrelated disorders; their associa- transposed them to right space (allo- tion (or dissociation) in individual patients chiria). This co-occurrence of neglect and could be due solely to an anatomical contiguity allochiria has been observed previously of discrete modules dedicated to "input" and but has provoked little theoretical com- "output" processes. There is, however, an ment. We draw attention to aspects of the emerging consensus,5 12 13 that the phenomena combination that seem critical to the may be two sides of the same coin. We describe interpretation of visuo-spatial neglect. a pertinent example of transposition by a patient who showed left neglect on traditional (7 Neurol Neurosurg Psychiatry 1992;55:717-719) testing. "Hemispatial neglect" is an appropriate Case report description for many of the symptoms dis- The patient is a 69 year old, right handed played by patients with right parietal damage. woman who had a right hemisphere stroke on Consider the patient who fails to cross out 22 October 1989. This resulted in a severe left target stimuli in contralesional space,' who sided hemiparesis and a marked loss of tactile bisects horizontal lines to the right of centre,2 sensation on the left (without tactile allochiria or who copies only the right side of a drawing.3 or allesthesia). There was neither a visual field Such cases neglect to process or respond to deficit nor nystagmus, although extinction to stimuli in a (variable) portion of visual hemi- bilateral simultaneous visual confrontation was http://jnnp.bmj.com/ space. Yet there is (at least) one aspect of the found. CT scan showed a large fronto-parietal performance of some of these patients for haemorrhage in the right hemisphere (fig 1). which the term "neglect" does not appear On admission to the Rivermead Rehabilitation entirely adequate. Centre on 19 February 1990, the outstanding For example, in tasks where the patient is neuropsychological symptom was gross left required to locate states or cities on a map, sided visual neglect. When she was examined targets may be displaced towards the ipsile- on the Behavioural Inattention Test (BIT)'4 in on September 26, 2021 by guest. Protected copyright. sional (right) side rather than simply omitted.3 A similar phenomenon is found on the familiar "bedside" task of drawing a clockface from Rivermead memory; some patients transpose all the num- Rehabilitation Centre, bers to the ipsilesional side.4 Similarly, on a Oxford, UK P W Halligan pointing task, patients may detect a left visual D T Wade field stimulus but erroneously point to it in the University right (ipsilesional) hemispace.5 Transpositions Department of can also be observed on purely "imaginal" Clinical Neurology, tasks; when describing a scene from memory The Radcliffe Infirmary, Oxford, UK (and a specified vantage point) some patients J C Marshall transpose features from the "neglected" to the Correspondence to: "good" side.4 Dr Marshall, University Phenomena of this general nature (alles- Department of Clinical Neurology, The Radcliffe thesia or allochiria) were first observed in the Infirmary, Oxford OX2 tactile modality6; a touch on the contralesional 6HE, UK side of the body is reported as occurring (often Received 16 September on the 1991 and in revised form in the symmetrical position) ipsilesional Figure 1 (CT scan showing a largefronto-parietal 11 November 1991. side.7 Similar referrals from left (affected) to Accepted 25 November haemorrhage in the right hemisphere. Left is on the right 1991 right (normal) space have been reported in of the image. 718 Halligan, Marshall, Wade J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.55.8.717 on 1 August 1992. Downloaded from May 1990, she scored 73/146. This aggregate drawing was displayed on the desk top imme- is based upon performance on: line crossing, diately above a blank sheet ofA4 on which the letter- and star-cancellation, figure copying, patient made her copy. The horizontal extent line bisection and representational drawing. of the complete butterfly (fig 2c) was 194 mm The cut-off score for normal performance is with a maximal height of 140 mm. The hor- 130/146. On star-cancellation (the most sen- izontal extent ofthe right and left butterfly (figs sitive test from the BIT), the patient failed to 2a and b) was 115 mm. For all stimuli the cross out any of 27 targets on the left of the body ofthe butterfly was always centred on the stimulus sheet and only succeeded in crossing page. No time limit was imposed; the patient out 12/27 on the right. Horizontal lines were inspected the stimulus and her copy until she bisected significantly to the right of centre. On was satisfied with her performance. copying simple geometric shapes, features on the left were consistently omitted. Asked to draw a clockface from memory, the Results patient's performance was variable. She always Stimulus fig 2a shows the butterfly with a drew a complete outline, but on one trial missing left wing. The patient reproduced the included only the appropriate six numbers on drawing accurately (fig 3a), omitting only one the right, whilst on two trials all twelve horizontal marking on the right wing. Stimulus numbers were placed along the right fig 2b has a missing right wing. It too is well hemicircumference. We accordingly devised a reproduced (fig 3b), although with some inac- new copying task to explore further such curacy in the number and orientation of the transpositions. lines on the wing. The copy of the full butterfly (fig 2c) is shown in fig 3c. It clearly shows that details of the left wing have been transposed Methods onto the right wing. The copy shows two sets of The stimuli comprised three images of a markings on the right wing, whereby the butterfly, drawn in black ink on white sheets of internal rings of the left wing of the original A4 (297 mm x 210 mm) paper. The drawings have been contrapositioned in "good" space. A were centred on the stimulus sheet and placed second set of three copies produced equivalent directly in front of the patient's midline. Each results. A A http://jnnp.bmj.com/ B B on September 26, 2021 by guest. Protected copyright. C C -:7 ( a ) Figure 2 Stimuli for copying; butterfly with missing left Figure 3 The patient's respective copies (3a, b, and c) of wing (a), missing right wing (b), andfull butterfly (c). the stimuli 2a, b, and c. Left on the right: allochiria in a case of left visuo-spatial neglect 719 J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.55.8.717 on 1 August 1992. Downloaded from Discussion parsing must be involved. Los Angeles is west It might be argued that "overelaboration" of of the east coast of the USA. Does that the right side of a copy may explain some description satisfy the patient's spatial cogni- forms of putative transposition. Gainotti and tion for map locations and thus cause "neg- Tiaccil5 were the first to report that many lect" of distance? The numbers on a clock patients with right hemisphere lesions tend to must be ordered from one to twelve. Could the overscore lines already copied from the right correct sequential order in itself satisfy the side of the stimulus configuration. A related patient's sense of "clockness" irrespective of phenomenon is seen on line cancellation tasks; position in space? In figure 3c, the butterfly patients with left neglect may fail to cross out does have two sets of markings, one to the left contralesional stimuli whilst making multiple of the other, and a central body. Is the patient's cancellations to lines in ipsilesional space.5 16 sense of "normal butterflyness" satisfied by This interpretation cannot apply to our present this configuration, and does she not require data. When the patient copies the one-winged that in a veridical copy one set of markings butterflies, there is no perseveration on any should also be left of the body? part of the drawing. It is only in the condition The history of art shows how different where a full butterfly is presented that trans- cultures can adopt different pictorial conven- position takes place. Furthermore, the trans- tions. The map of the London Underground is position phenomenon is not constant; on perfectly adequate for its intended function; cancellation tasks and on copying a symmet- but anyone who attempted to use it on the rical four-pointed star and flower, the patient surface would be seriously misled. Likewise, made left-sided omissions. In a patient whose the conceptual schema of the patient with tendency to transpose is less variable, it would "neglect" may be satisfied by pictorial objects be pertinent to investigate the effects of stim- that represent only a subset of geometric ulus symmetry on allochiria.