Classification of Graphomotor Impressions Using Convolutional Neural Networks: An Application to Automated Neuro-Psychological Screening Tests

Graphomotor impressions are a product of complex cognitive, perceptual and motor skills and are widely used as psychometric tools for the diagnosis of a variety of neuro-psychological disorders. Apparent deformations in these responses are quantified as errors and are used are indicators of various conditions. Contrary to conventional assessment methods where manual analysis of impressions is carried out by trained clinicians, an automated scoring system is marked by several challenges. Prior to analysis, such computerized systems need to extract and recognize individual shapes drawn by subjects on a sheet of paper as an important pre-processing step. The aim of this study is to apply deep learning methods to recognize visual structures of interest produced by subjects. Experiments on figures of Bender Gestalt Test (BGT), a screening test for visuo-spatial and visuo-constructive disorders, produced by 120 subjects, demonstrate that deep feature representation brings significant improvements over classical approaches. The study is intended to be extended to discriminate coherent visual structures between produced figures and expected prototypes

Room for chaos? : authenticity and performance in undergraduate spatial design students’ accounts of ideational work

A thesis submitted to the University of Bedfordshire, in fulfilment of the requirements for the degree of Professional DoctorateThis study was prompted by my suspicion that spatial design undergraduates’ production of paper-based freehand sketches during design ideation was in decline. Seeking to find out why, I conducted video-recorded focused interviews with undergraduates from a range of UK spatial design degrees, during which we examined their sketchbook material and discussed their ideational activities (termed ‘ideational moves’). I subjected the data to a form of content analysis, but the outcomes appeared to contradict my initial premise whilst revealing that the interactions during the interviews between myself, the respondents and the sketchbook material (termed ‘discursive moves’) warranted examination. This persuaded me that the study’s focus should emerge through ‘evolved’ grounded theory rather than being stated a priori, which highlighted my presence in, and impact on, the data and prompted me to adopt a constructivist grounded theorising approach in combination with actor-network theory’s concepts of translation and circulating references. This study has thus been qualitative, relativist, iterative and multi-modal. Grounded theorising led to the identification of a number of categories and sub-categories of ideational move across the sample, and indicated that the respondents had used a ‘core’ of each. ‘Core’ categories comprised: making paper-based ideational moves, carrying out research and using photographic material. Several respondents also evidenced producing digital imagery and physical models. ‘Core’ sub-categories comprised using paper-based freehand perspective sketches, sketch diagrams and word-based approaches, plus supporting visuo-spatial research. Several respondents also evidenced producing paper-based freehand plan, section and elevation sketches, plus collage. Grounded theorising also revealed that each respondent had utilised a different combination of sub-categories, with different degrees of connectedness. I did not set out to evaluate the design outcomes showcased, but, as a spatial design academic and practitioner, I felt compelled to. This led to the tentative conclusion that respondents who added to the ‘core’ of categories and sub-categories and worked with greater connectedness appeared to produce more thoroughly-considered work, whilst those who forsook the ‘core’ and worked with less connectedness appeared to produce more unexpected results by allowing ‘…room for chaos…’: periods of confusion and surprise. Regarding the discursive moves, grounded theorising indicated that the sketchbook material tabled by each respondent during the study was not one fixed thing, but an abstraction using placing-for and directing-to techniques to focus attention on certain ideational moves and away from others. This made the sketchbook material a performance within the network of human and non-human actors who, in effect, co-constructed it as a temporary reality without necessarily realising this. Research into sketchbook material appears to regard it, once shared with others, as having the candour of a secret diary, and as eligible for formative and summative assessment because it documents design process authentically. My study, whilst not claiming generalisability, suggests that this view should be challenged. The new knowledge is now informing my future teaching practice and will, I hope, prompt other academics to investigate whether their own students manifest similar outcomes and, through this, contribute to wider discussions on the formative and summative assessment of undergraduate spatial design development activity

IDATER online conference: graphicacy and modelling 2010

IDATER online conference: graphicacy and modelling 201

Designers Who Don’t Draw: An Investigation into Sketch Inhibition among Undergraduate Designers

Sketch inhibition in undergraduate designers is a phenomenon widely acknowledged by educators, yet one garnering little attention from the academy. Defined as a reluctance or inability to use sketching effectively, it impacts negatively upon design ideation and the representation, evaluation and communication of information essential for successful design. The uniqueness of sketching was confirmed by the study; as a personalised icon-based language, a method of cognitive support for mental imagery and a tool for analysis. Ideation - the combination of intrinsically linked micro-activities within mental imagery and their representation - relies upon effective offloading of the working memory, the sketch being an irreplaceable tool for this purpose. Sketch inhibition is a complex behavioural phenomenon with single or multiple causes. These include, but are not limited to, skill-set deficiency, social anxiety and previous negative educational experience. Symptoms include reluctance to engage, deferral to other tools and poor quality design output. Effects are embodied in the inability to conceptualise and develop design information effectively, with impact graduate employability and commercial activity. Although purported to be integral to design higher education, considerable problems exist regarding its teaching and use at strategic, institutional and pedagogic levels. This includes the erroneous assumption that sketching is an intuitive activity that need not be taught. Examples of best practice suggest that, much like language, it needs to be formally taught and practised in order to develop both vocabulary and fluency in its use, in order that it can support design ideation successfully. This study applies a Grounded Theory approach to investigation of sketch inhibition and subsequently formulates a theory of the phenomenon. A pedagogic framework for sketch inhibition within design education is presented and evaluated, suggesting the command of it is possible - and on the part of the sufferer, even enjoyable.De Montfort Universit

Drawing, Handwriting Processing Analysis: New Advances and Challenges

International audienceDrawing and handwriting are communicational skills that are fundamental in geopolitical, ideological and technological evolutions of all time. drawingand handwriting are still useful in defining innovative applications in numerous fields. In this regard, researchers have to solve new problems like those related to the manner in which drawing and handwriting become an efficient way to command various connected objects; or to validate graphomotor skills as evident and objective sources of data useful in the study of human beings, their capabilities and their limits from birth to decline

Automatic interpretation of clock drawings for computerised assessment of dementia

The clock drawing test (CDT) is a standard neurological test for detection of cognitive impairment. A computerised version of the test has potential to improve test accessibility and accuracy. CDT sketch interpretation is one of the first stages in the analysis of the computerised test. It produces a set of recognised digits and symbols together with their positions on the clock face. Subsequently, these are used in the test scoring. This is a challenging problem because the average CDT taker has a high likelihood of cognitive impairment, and writing is one of the first functional activities to be affected. Current interpretation systems perform less well on this kind of data due to its unintelligibility. In this thesis, a novel automatic interpretation system for CDT sketch is proposed and developed. The proposed interpretation system and all the related algorithms developed in this thesis are evaluated using a CDT data set collected for this study. This data consist of two sets, the first set consisting of 65 drawings made by healthy people, and the second consisting of 100 drawings reproduced from drawings of dementia patients. This thesis has four main contributions. The first is a conceptual model of the proposed CDT sketch interpretation system based on integrating prior knowledge of the expected CDT sketch structure and human reasoning into the drawing interpretation system. The second is a novel CDT sketch segmentation algorithm based on supervised machine learning and a new set of temporal and spatial features automatically extracted from the CDT data. The evaluation of the proposed method shows that it outperforms the current state-of-the-art method for CDT drawing segmentation. The third contribution is a new v handwritten digit recognition algorithm based on a set of static and dynamic features extracted from handwritten data. The algorithm combines two classifiers, fuzzy k-nearest neighbour’s classifier with a Convolutional Neural Network (CNN), which take advantage both of static and dynamic data representation. The proposed digit recognition algorithm is shown to outperform each classifier individually in terms of recognition accuracy. The final contribution of this study is the probabilistic Situational Bayesian Network (SBN), which is a new hierarchical probabilistic model for addressing the problem of fusing diverse data sources, such as CDT sketches created by healthy volunteers and dementia patients, in a probabilistic Bayesian network. The evaluation of the proposed SBN-based CDT sketch interpretation system on CDT data shows highly promising results, with 100% recognition accuracy for heathy CDT drawings and 97.15% for dementia data. To conclude, the proposed automatic CDT sketch interpretation system shows high accuracy in terms of recognising different sketch objects and thus paves the way for further research in dementia and clinical computer-assisted diagnosis of dementia

Haptics: Science, Technology, Applications

This open access book constitutes the proceedings of the 12th International Conference on Human Haptic Sensing and Touch Enabled Computer Applications, EuroHaptics 2020, held in Leiden, The Netherlands, in September 2020. The 60 papers presented in this volume were carefully reviewed and selected from 111 submissions. The were organized in topical sections on haptic science, haptic technology, and haptic applications. This year's focus is on accessibility

How sketches work: a cognitive theory for improved system design

Evidence is presented that in the early stages of design or composition the mental processes used by artists for visual invention require a different type of support from those used for visualising a nearly complete object. Most research into machine visualisation has as its goal the production of realistic images which simulate the light pattern presented to the retina by real objects. In contrast sketch attributes preserve the results of cognitive processing which can be used interactively to amplify visual thought. The traditional attributes of sketches include many types of indeterminacy which may reflect the artist's need to be "vague". Drawing on contemporary theories of visual cognition and neuroscience this study discusses in detail the evidence for the following functions which are better served by rough sketches than by the very realistic imagery favoured in machine visualising systems. 1. Sketches are intermediate representational types which facilitate the mental translation between descriptive and depictive modes of representing visual thought. 2. Sketch attributes exploit automatic processes of perceptual retrieval and object recognition to improve the availability of tacit knowledge for visual invention. 3. Sketches are percept-image hybrids. The incomplete physical attributes of sketches elicit and stabilise a stream of super-imposed mental images which amplify inventive thought. 4. By segregating and isolating meaningful components of visual experience, sketches may assist the user to attend selectively to a limited part of a visual task, freeing otherwise over-loaded cognitive resources for visual thought. 5. Sequences of sketches and sketching acts support the short term episodic memory for cognitive actions. This assists creativity, providing voluntary control over highly practised mental processes which can otherwise become stereotyped. An attempt is made to unite the five hypothetical functions. Drawing on the Baddeley and Hitch model of working memory, it is speculated that the five functions may be related to a limited capacity monitoring mechanism which makes tacit visual knowledge explicitly available for conscious control and manipulation. It is suggested that the resources available to the human brain for imagining nonexistent objects are a cultural adaptation of visual mechanisms which evolved in early hominids for responding to confusing or incomplete stimuli from immediately present objects and events. Sketches are cultural inventions which artificially mimic aspects of such stimuli in order to capture these shared resources for the different purpose of imagining objects which do not yet exist. Finally the implications of the theory for the design of improved machine systems is discussed. The untidy attributes of traditional sketches are revealed to include cultural inventions which serve subtle cognitive functions. However traditional media have many short-comings which it should be possible to correct with new technology. Existing machine systems for sketching tend to imitate nonselectively the media bound properties of sketches without regard to the functions they serve. This may prove to be a mistake. It is concluded that new system designs are needed in which meaningfully structured data and specialised imagery amplify without interference or replacement the impressive but limited creative resources of the visual brain