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Motor aspects of handwriting: approaches to movement in graphic behavior
Book reviews
161
These, however, are small snags in a stimulating book, and mention must also be made of four computer programs in BASIC language, which aid in the solution of some difficult cases investigated in the main text. These programs evaluate the moments of inertia of the runner’s leg, the length and optimum projection angle in a throw or jump, and the success or failure of a basketball free throw. They are written in interactive form, and disk versions are available for purchase from the publisher. A.J. Smith
Reading about writing A.J.W.M. Thomassen, P.J.G. Keuss and G.P. van Galen (eds.), Motor aspects of handwriting: approaches to movement in graphic behavior. Amsterdam: North-Holland, 1984. pp. 354, US $50.00/Dfl.130.00. Handwriting is a human skill, a fundamental form of communication effected through the hands, and systematic evaluation of the relationship between how information is communicated and the structure of the information being communicated is likely to be very fruitful. Reprinted from Acta Psychologica (Vol. 54, 1983), Motor Aspects of Handwriting is a diverse collection of empirical papers selected from an International Workshop held in July, 1982, by the Department of Experimental Psychology, University of Nijmegen, The Netherlands. Of the 21 reports, 6 are from Nijmegen or Amsterdam, 4 represent collaborative efforts of Nijmegen researchers with others, and 11 are from other universities or research laboratories. There are multiple contributions from Kao, Teulings, Thomassen, van Galen and Wing. The papers are organized into five sections: (1) motor theory, (2) biophysical approaches, (3) contextual factors in grapheme retrieval and performance, (4) development, learning and pathology, and (5) perceptual-motor aspects of handwriting. As often occurs with edited volumes, the papers grouped in each section do not always fit clearly together and transitions are difficult since the authors have different theoretical orientations, empirical approaches, levels of analysis and they occasionally display inconsistent use of terms (e.g., grapheme, allograph, graph etc.). To aid the reader, the editors provide a clear
162
Book reurews
overview of the 3-5 papers in each section, with appropriate links outlined. While the volume contents are listed alphabetically by author at the back of the book, a Table of Contents is notably absent, making retrieval of a specific paper difficult unless one remembers the authors. In addition there are an author index and a helpful but limited subject index. Most of the papers have a strong psychonomic orientation (laws of mental processes), thus creating a context in which the reader is refreshed by ergonomic (Suen), developmental (Nihei) and neuropsychological (Margolin and Wing) contributions. A diversity of methods and measures are employed. Measures range from traditional, accuracy and time-based psychonomic ones (reaction time, movement duration, number of letters produced per unit time, number correctly recognized, etc.) through kinematic analyses of pen tip on digitizing tablets, and measures of pressure on the writing surface and along the axis of the pen, to the evaluation and categorization of visuospatial form and legibility. The book is a rich source of ingenious experimental manipulations, computer simulation and observational methods, Yet, the reader might have the uneasy feeling that many of the findings are not easily generalizable to writing in more natural situations and conditions (see the section on context effects). The populations were not as diverse as the methods or measures: only five papers studied other than right-handed university adults. Departing from the study of normal handwriting, Margolin and Wing studied Parkinsonian patients with micrographia (small writing, inferred to reflect a diminuition in ‘effective force’) in which the spatial orientation of letters was intact, and a stroke patient with acquired agraphia (a writing deficit, inferred to reflect a praxic processing dysfunction relating to the spatial orientation of letters, i.e., graphic motor pattern problem). They suggest that handwriting skill has anatomically and functionally separable subcomponents, which could be more clearly identified through neuropsychological evaluation of the component processes in handwriting disorders. Three of the papers examined the ontogenetic development of handwriting (Thomassen and Teulings; Nihei; Sovik and Teulings). More specifically, Nihei examined the organization of strokes for over 2000 children printing Hiragana, the simplest of Japanese writing forms. He identified systematic developmental changes in the spatial and serial organization of strokes. Moreover, he noted that the structure
of the letter constrains the organization of strokes. Only one paper specifically examined left-handers: Suen found no differences between left-‘and right-handers in the speed of generating cursive, manuscript and block print, yet there were legibility differences. Handwriting of left-handers was more difficult to recognize than handwriting of right-handers, and left-handers were not as good as right-handers at recognizing letters. While Suen had no explanation for these findings, it might be of interest to consider that although the visual pattern (letters) to be produced is the same regardless of handedness, abductive hand movements for right-handers correspond to adductive hand movements of left-handers during the process of handwriting. In addition, left-handers adopt a variety of hand postures relative to right-handers, and this affects letter orientation and writing slant. Writing slant and letter orientation can be affected by orientation of the page as well as posture of the hand. Only 3 of the papers in Motor Aspects of Handwriting contained a statement clarifying the position of the paper when an X, Y digitizing tablet was used (Pick and Teulings; Stelmach and Teulings; Teulings). Maarse and Thomassen discuss the dominance of downstrokes over upstrokes in handwriting, both in production (as a function of horizontal space constraints), and in perception of handwriting slant. Valuable additions would include manipulation of the orientation of the page and left-handed subjects. The papers on typewriting (Gentner; Grudin) are notable in Motor Aspects of Handwriting, since a consideration of similarities and differences between the two forms of writing suggest two main themes. First, how are they effected? Although handwriting and typewriting require the use of (one or two) hands, typewriting has more observable hand and individual finger movements to strike the keys (both Gentner and Grudin report finger trajectories). In contrast, Grudin notes that writing involves the whole hand, and the same muscles are involved in the formation of different letters. It seems that there is minimal overt movement of the hand in handwriting, and lever length magnifies movement of the pen on the page. While some authors (van Galen and Teulings, p. 11; the editors, p. 79; Maarse and Thomassen, p. 131; see especially Thomassen and Teulings, p. 180-181) address the anatomical and physical relationships of the handwriting movement, it is clear that these need to be empirically evaluated, especially as they relate to handwriting form on the page. Are finger and intrinsic hand muscles
responsible for pen motion/letter formation (or its vertical component only), independent or more proximal muscles? What are the roles of wrist, forearm and shoulder muscles for (the horizontal components of) letter formation, for transition strokes between letters in cursive writing and for left-to-right progression across the page? Thomassen and Teulings conduct experiments showing that left to right progression is not simply superimposed on letter shape components (cross-cultural studies of slant and stroke characteristics for written language with a right-toleft progression are needed). Pick and Teulings argue that horizontal and vertical components of handwriting cannot be independently modified with respect to size. Their data suggests this may be the case also for orientation. The second main theme, consolidated by the contrast of typewriting with handwriting, concerns the level of analysis, and the appropriate units. In Motor Aspects of Handwriting, we read about context specific: muscle parameters, synergistic muscle groups, control units, strokes, visuospatial motor patterns, graphs, allographs, graphemes, letters, geometric forms. There is debate whether strokes, allographs, letters, graphemes, etc. are the relevant units. Each is likely the relevant unit for a given level of analysis. For handwriting and typewriting, linguistic, motor, spatiotemporal and manual components are common. Grudin (p. 261) suggests that substitution errors in typing (one letter for another) have a parallel of switch errors in handwriting (where strokes from subsequent letters appear in current letters and the writer continues with strokes for the subsequent letter). Further, the ‘simultaneous activation of motor representations of successive letters’ gives rise to errors observed in typing and handwriting. The notion of simultaneous activation of successive letters implies parallel processing of linguistic, motor, spatiotemporal and manual components in handwriting. The editors of Motor Aspects of Handwriting acknowledge the divergent methods and different levels of inquiry. On the one hand, the specificity of individual papers makes reading and integration difficult; on the other hand, this diversity is rich and thought provoking. The book is thus an excellent tool and recommended for those interested in research on human skills, Christine
L. MacKenzie Sylvie Athenes
161
These, however, are small snags in a stimulating book, and mention must also be made of four computer programs in BASIC language, which aid in the solution of some difficult cases investigated in the main text. These programs evaluate the moments of inertia of the runner’s leg, the length and optimum projection angle in a throw or jump, and the success or failure of a basketball free throw. They are written in interactive form, and disk versions are available for purchase from the publisher. A.J. Smith
Reading about writing A.J.W.M. Thomassen, P.J.G. Keuss and G.P. van Galen (eds.), Motor aspects of handwriting: approaches to movement in graphic behavior. Amsterdam: North-Holland, 1984. pp. 354, US $50.00/Dfl.130.00. Handwriting is a human skill, a fundamental form of communication effected through the hands, and systematic evaluation of the relationship between how information is communicated and the structure of the information being communicated is likely to be very fruitful. Reprinted from Acta Psychologica (Vol. 54, 1983), Motor Aspects of Handwriting is a diverse collection of empirical papers selected from an International Workshop held in July, 1982, by the Department of Experimental Psychology, University of Nijmegen, The Netherlands. Of the 21 reports, 6 are from Nijmegen or Amsterdam, 4 represent collaborative efforts of Nijmegen researchers with others, and 11 are from other universities or research laboratories. There are multiple contributions from Kao, Teulings, Thomassen, van Galen and Wing. The papers are organized into five sections: (1) motor theory, (2) biophysical approaches, (3) contextual factors in grapheme retrieval and performance, (4) development, learning and pathology, and (5) perceptual-motor aspects of handwriting. As often occurs with edited volumes, the papers grouped in each section do not always fit clearly together and transitions are difficult since the authors have different theoretical orientations, empirical approaches, levels of analysis and they occasionally display inconsistent use of terms (e.g., grapheme, allograph, graph etc.). To aid the reader, the editors provide a clear
162
Book reurews
overview of the 3-5 papers in each section, with appropriate links outlined. While the volume contents are listed alphabetically by author at the back of the book, a Table of Contents is notably absent, making retrieval of a specific paper difficult unless one remembers the authors. In addition there are an author index and a helpful but limited subject index. Most of the papers have a strong psychonomic orientation (laws of mental processes), thus creating a context in which the reader is refreshed by ergonomic (Suen), developmental (Nihei) and neuropsychological (Margolin and Wing) contributions. A diversity of methods and measures are employed. Measures range from traditional, accuracy and time-based psychonomic ones (reaction time, movement duration, number of letters produced per unit time, number correctly recognized, etc.) through kinematic analyses of pen tip on digitizing tablets, and measures of pressure on the writing surface and along the axis of the pen, to the evaluation and categorization of visuospatial form and legibility. The book is a rich source of ingenious experimental manipulations, computer simulation and observational methods, Yet, the reader might have the uneasy feeling that many of the findings are not easily generalizable to writing in more natural situations and conditions (see the section on context effects). The populations were not as diverse as the methods or measures: only five papers studied other than right-handed university adults. Departing from the study of normal handwriting, Margolin and Wing studied Parkinsonian patients with micrographia (small writing, inferred to reflect a diminuition in ‘effective force’) in which the spatial orientation of letters was intact, and a stroke patient with acquired agraphia (a writing deficit, inferred to reflect a praxic processing dysfunction relating to the spatial orientation of letters, i.e., graphic motor pattern problem). They suggest that handwriting skill has anatomically and functionally separable subcomponents, which could be more clearly identified through neuropsychological evaluation of the component processes in handwriting disorders. Three of the papers examined the ontogenetic development of handwriting (Thomassen and Teulings; Nihei; Sovik and Teulings). More specifically, Nihei examined the organization of strokes for over 2000 children printing Hiragana, the simplest of Japanese writing forms. He identified systematic developmental changes in the spatial and serial organization of strokes. Moreover, he noted that the structure
of the letter constrains the organization of strokes. Only one paper specifically examined left-handers: Suen found no differences between left-‘and right-handers in the speed of generating cursive, manuscript and block print, yet there were legibility differences. Handwriting of left-handers was more difficult to recognize than handwriting of right-handers, and left-handers were not as good as right-handers at recognizing letters. While Suen had no explanation for these findings, it might be of interest to consider that although the visual pattern (letters) to be produced is the same regardless of handedness, abductive hand movements for right-handers correspond to adductive hand movements of left-handers during the process of handwriting. In addition, left-handers adopt a variety of hand postures relative to right-handers, and this affects letter orientation and writing slant. Writing slant and letter orientation can be affected by orientation of the page as well as posture of the hand. Only 3 of the papers in Motor Aspects of Handwriting contained a statement clarifying the position of the paper when an X, Y digitizing tablet was used (Pick and Teulings; Stelmach and Teulings; Teulings). Maarse and Thomassen discuss the dominance of downstrokes over upstrokes in handwriting, both in production (as a function of horizontal space constraints), and in perception of handwriting slant. Valuable additions would include manipulation of the orientation of the page and left-handed subjects. The papers on typewriting (Gentner; Grudin) are notable in Motor Aspects of Handwriting, since a consideration of similarities and differences between the two forms of writing suggest two main themes. First, how are they effected? Although handwriting and typewriting require the use of (one or two) hands, typewriting has more observable hand and individual finger movements to strike the keys (both Gentner and Grudin report finger trajectories). In contrast, Grudin notes that writing involves the whole hand, and the same muscles are involved in the formation of different letters. It seems that there is minimal overt movement of the hand in handwriting, and lever length magnifies movement of the pen on the page. While some authors (van Galen and Teulings, p. 11; the editors, p. 79; Maarse and Thomassen, p. 131; see especially Thomassen and Teulings, p. 180-181) address the anatomical and physical relationships of the handwriting movement, it is clear that these need to be empirically evaluated, especially as they relate to handwriting form on the page. Are finger and intrinsic hand muscles
responsible for pen motion/letter formation (or its vertical component only), independent or more proximal muscles? What are the roles of wrist, forearm and shoulder muscles for (the horizontal components of) letter formation, for transition strokes between letters in cursive writing and for left-to-right progression across the page? Thomassen and Teulings conduct experiments showing that left to right progression is not simply superimposed on letter shape components (cross-cultural studies of slant and stroke characteristics for written language with a right-toleft progression are needed). Pick and Teulings argue that horizontal and vertical components of handwriting cannot be independently modified with respect to size. Their data suggests this may be the case also for orientation. The second main theme, consolidated by the contrast of typewriting with handwriting, concerns the level of analysis, and the appropriate units. In Motor Aspects of Handwriting, we read about context specific: muscle parameters, synergistic muscle groups, control units, strokes, visuospatial motor patterns, graphs, allographs, graphemes, letters, geometric forms. There is debate whether strokes, allographs, letters, graphemes, etc. are the relevant units. Each is likely the relevant unit for a given level of analysis. For handwriting and typewriting, linguistic, motor, spatiotemporal and manual components are common. Grudin (p. 261) suggests that substitution errors in typing (one letter for another) have a parallel of switch errors in handwriting (where strokes from subsequent letters appear in current letters and the writer continues with strokes for the subsequent letter). Further, the ‘simultaneous activation of motor representations of successive letters’ gives rise to errors observed in typing and handwriting. The notion of simultaneous activation of successive letters implies parallel processing of linguistic, motor, spatiotemporal and manual components in handwriting. The editors of Motor Aspects of Handwriting acknowledge the divergent methods and different levels of inquiry. On the one hand, the specificity of individual papers makes reading and integration difficult; on the other hand, this diversity is rich and thought provoking. The book is thus an excellent tool and recommended for those interested in research on human skills, Christine
L. MacKenzie Sylvie Athenes