Utilization behaviour has previously been described clinically by Lhermitte (1983). An experimental investigation is reported of utilization behaviour in a patient with a localized inferior medial bifrontal lesion. The patient picked up and used irrelevant objects not only when place directly in front of him--the procedure developed by Lhermitte--but also when he had been instructed to carry out other tasks and his attention had not been directed to the objects. The behaviour occurred most frequently in the brief intervals between tasks, and more often when auditory-verbal rather than visuomotor tasks were being performed. The results are interpreted within an information-processing model of frontal lobe function. A differentiation is made between two forms of utilization behaviour--an 'incidental' form, as exhibited by the patient, and an 'induced' form where it occurs only when Lhermitte's procedure is adopted.

No abstract

SUMMARY A case study investigates the writing, spelling and praxic skills of one patient who was found to have a selective impairment in his ability to write letters and words in the absence of difficulty in copying these same letters and words. He appeared to have difficulty accessing the correct motor programmes or sequences for writing which we term "ideational agraphia" analagous to the syndrome of ideational apraxia. These findings are related to Margolin's informationprocessing model of writing.The concept of "pure agraphia" as a unitary syndrome has long been superseded by the documentation of a number of distinct subtypes of agraphia. Inherent in an accurate classification of the agraphias is the distinction between the disorders of "spelling" and disorders of "writing". In the spelling agraphias there is a disturbance of letter choice but the actual written form of letters remains intact. The majority of these cases show little or no difference between oral and written spelling skills, unless associated deficits are also present. In contrast, patients with disorders of writing or apraxic agraphia do not have problems with letter-name selection as such. The deficit cannot be explained by peripheral weakness or clumsiness, by sensory problems or by confusion or impaired reasoning. The identification of "pure" apraxic agraphia requires a disturbance of writing in the absence of a disturbance of spelling, reading or other general language problems. More importantly, it should occur in the absence of major praxic or visuo-constructional difficulties.To our knowledge, no reports providing quantitative data fulfilling the above criteria have been published (for a review see ref 1), although there are a number of cases which include apraxic agraphia as a major feature (for example, in refs 2-5, amongst others). The following systematic investigation describes a patient with a marked disturbance of writing in the absence of any impairment of oral spelling, praxic or visuo-constructional difficulties, thus fulfilling the above requirements of a "pure" apraxic agraphic. Case report IDT, a 73-year-old retired production engineer was transferred for further investigations on 2 May 1985. He was fully right handed for writing and for all tasks involving both motor agility and motor power. Since December 1984 he had experienced increasing difficulties with memory, his conversation had become "woolly" and he had even lost his way when driving in a familiar district. His writing had deteriorated and since March he had been unable to write at all.On examination there was no evidence of papilloedema or visual field loss. His cranial nerves, motor system and reflexes were all normal. No definite sensory loss was present although two-point discrimination was a little variable on the right hand (right index finger 5mm, left 4 mm). He was, however, totally disorientated in time and place. He was unable to give a history and had forgotten his home address. Apart from his very obvious global memory impairments he had an agraphia...

In this paper we describe the construction of a graded-difficulty spelling test for adults consisting of two alternative forms each containing 30 words (GDST, Forms A and B). The spelling test, together with background tests of verbal and non-verbal skills, was administered to 100 control patients with orthopaedic injuries. The two forms of the spelling test were highly correlated (0.92). Spelling was highly correlated with reading (0.75, 0.77) and moderately correlated with vocabulary (0.57) and naming (0.39, 0.40). There was no correlation between spelling skills and non-verbal reasoning. The test was validated in a group of 26 patients with left hemisphere and 20 patients with right hemisphere lesions. Spelling was shown to be lateralized to the left hemisphere and there appeared to be a shift in scores of the left hemisphere group towards the lower quartile, with 65% of the left hemisphere group falling within this band. The most severe spelling impairments were invariably associated with other language disorders but a number of dissociations were documented at spelling levels falling between the 5th and 25th percentile band. Two patients with left hemisphere lesions (8%) were identified as having selective dysgraphias. The lack of overlap between the anatomical sites of the two patients with specific lexical dysgraphia argues against a single site for this type of dysgraphia and argues for further refinement of this classification of spelling disorder.

We report a detailed analysis of the written spelling of an aphasic patient, KT, in whom no viable comprehension could be demonstrated despite accurate repetition and fluent speech (transcortical sensory aphasia). His spelling conformed in all respects with the definition of an orthographic/lexical dysgraphic such that his writing of regular, orthographically unambiguous words and nonsense syllables was entirely satisfactory. Lexical variables such as word class or word frequency had no effect on his performance. Irregular or ambiguously spelled words were selectively impaired. An independent measure of orthographical ambiguity was defined in relation to the frequency with which a phoneme was represented by a particular grapheme and the number of alternative graphemes for the same sound. For the majority of sounds studied, KT was able to demonstrate the use of all the most frequent alternative transcoding units for each sound but he did not use them in the same frequency with which they occurred in written English. Thus his performance bore little or no relationship to predictions based on single phoneme/grapheme counts and there was unequivocal evidence for his ability to use multiple sound-unit correspondences.