Attention responsive technology and ergonomics

The ART (Attention-Responsive Technology) research project is developing a system to enable mobility-impaired individuals to access technology efficiently. The system monitors both the individual and any ICT devices in his/her environment. It then uses the individual’s gaze direction to determine to which ICT device they are potentially attending. This information is relayed to a user-configurable control panel, which then displays only those controls that are appropriate, both to the user and to the particular device in question. The user can then choose to operate the device if s/he wishes. The initial ergonomic challenges in the development of the ART system are described

The role of eye movements in the figure perception

The figure-ground distinction is particularly interesting where the same stimulus can give rise to more than the one interpretation of figure. The work presented here examines the role of eye movements in such figure perception. The figure-ground dichotomy is first elaborated and stimuli which can give different figural interpretations are classified as reversible perspective or ambiguous figures. Theories which have been proposed to account for such figure perception are then reviewed and it is argued that a schematic map theory offers a plausible explanation. The parameters which have been studied with regard to these stimuli are then considered and it is argued that the role of eye movements has not been adequately investigated. Stimuli are then proposed to be composed of elements which are differentially weighted towards each figural aspect. Figure perception is largely a result of an observer selectively attending to these elements as determined by the schematic map. Eye movements function to move such attention about the stimulus. A series of afterimage experiments then examines the existence of such elements in a line drawing of Boring's ambiguous figure. The response of figure was found to be governed by the elements to which the subject could attend. Two free-viewing experiments are then reported which demonstrated that in a non- stabilised condition the immediate response of figure was determined by the elements present in the stimulus. No age-related effects of such elements were found when children served as subjects. Eye movement types and recording techniques are then reviewed and an inconspicuous recording method developed. Subjects' eye movements were then recorded as they viewed versions of the ambiguous figure. The results are interpreted as supporting a schematic map explanation. A model is finally developed to account for the role of eye movements in figure perception

Maintaining quality in the UK breast screening program

Breast screening in the UK has been implemented for over 20 years and annually nearly two million women are now screened with an estimated 1,400 lives saved. Nationally, some 700 individuals interpret screening mammograms in almost 110 screening centres. Currently, women aged 50 to 70 are invited for screening every three years and by 2012 this age range will increase to 47 - 73 years. There is a rapid ongoing transition from using film mammograms to full field digital mammography such that in 2010 every screening centre will be partly digital. An early, and long running, concern has been how to ensure the highest quality of imaging interpretation across the UK, an issue enhanced by the use of a three year screening interval. To partly address this question a self assessment scheme was developed in 1988 and subsequently implemented nationally in the UK as a virtually mandatory activity. The scheme is detailed from its beginnings, through its various developments to current incarnation and future plans. This encompasses both radiological (single view screening, two view screening, mammographic film and full field digital mammography) as well as design changes (cases reported by means of: form filling; PDA; tablet PC; iPhone, and the internet). The scheme provides a rich data source which is regularly studied to examine different aspects of radiological performance. Overall it aids screening radiologists by giving them regular access to a range of difficult exemplar cases together with feedback on their performance as compared to their peers

PERFORMS - a self assessment scheme for radiologists in breast screening

A difficulty for any radiologist involved in breast screening is to know how well he or she is performing, given the low incidence of the disease. The latest available UK data indicate a breast cancer rate of circa 6.8% per 1,000, within the screened population of 50-64 year old women1. Some 15 years ago when the UK Breast Screening Programme was established it was recommended that a radiologist should read 6,000 cases a year2. The Royal College of Radiologists subsequently amended this figure to 5,000 cases3 although several radiologists read many more cases than this – exceeding 20,000 annually and in rare cases up to 30,000. A similar recommendation of 5,000 cases per annum exists in other European countries4 although in some countries, such as the USA, the number is much lower, circa 4805

The role of ultrasound in breast screening

Ultrasound is a valuable diagnostic tool commonly used by Radiologists in breast screening. The current paper outlines the main functions that Ultrasound performs, differences between mammography and Ultrasound and why it is a topic worthy of ergonomic and psychological research. Finally, a summary of the various methodological approaches to studying Ultrasound usage and interpretation are outlined which will be used to inform the development of a new Ultrasound training application to be used by trainee radiologists

Environmental control by remote eye tracking

Eye movement interfacing can be found in some specially designed environmental control systems (ECSs) for people with severe disability. Typically this requires the user to sit in front of a computer monitor and their eye gaze direction is then detected which controls the cursor position on the screen. The ECS screen usually consists of a number of icons representing different controllable devices and an eye fixation landing within a pre-defined icon area then activates a selection for control. Such systems are widely used in homes, offices, schools, hospitals, and long-term care facilities. Wellings and Unsworth (1997) demonstrated that a user-friendly interface design is the weak link in ECS technology, in particular for severely disabled people. Disabled individuals need straightforward control of their immediate surroundings and so making a detailed menu selection by techniques, such as eye-screen interaction, can be a difficult and tedious process for some individuals. This situation can be exasperated by real-world issues such as eye tracking systems which do not tolerate user’s head movement. This paper presents a different approach to environmental control using eye gaze selection, in which the control options applicable to a given device are automatically pre-selected by means of the user directly looking at the device in their environment. This intuitive method therefore minimises the amount of navigation that the user must perform. To date, two main methods have been employed to achieve this direct eye-device control. The initial development using a head-mounted eye tracker was previously reported (Shi et al., 2006). This current paper describes subsequent development of the system (Shi et al., 2007) using a remote eye tracker which is simply situated before the user with no need for any attachment to them

Look in, turn on, drop out

The ART (Attention-Responsive Technology) research project is developing a system to enable mobility-impaired individuals to access technology efficiently. The system monitors both the individual and any ICT devices in his/her environment. It then uses the individual’s gaze direction to determine to which ICT device, if any, they are potentially attending. This information is relayed to a userconfigurable control panel, which then displays only those controls that are appropriate, both to the user and to the particular device in question. The user can then choose to operate the device if s/he wishes. The initial ergonomic challenges in the development of the ART system are described

Does mammographic practice affect film reading style - breast screening vs. symptomatic radiologists?

In the UK there are two groups of radiologists who routinely read mammographic cases: Symptomatic and Screening Radiologists. We examined the performance of these two film-reading populations, Breast Screening Radiologists and Symptomatic Radiologists, to evaluate if there were group differences in their ‘style’ of reading the same set of cases. Specifically we looked at each group’s sensitivity and specificity measures. In addition we investigated if there were any individual group differences apparent in the cases which they found challenging and what (if any) were the characteristics of those cases. Data from 66 Breast Screening Radiologists and a matched group of 66 Symptomatic Radiologists were compared over a number of years (360 cases). Results are presented which demonstrate that whilst the two groups show overall similarities in performance there exist subtle underlying differences which we attribute to the differences in their everyday experience of the types of cases that they read. In conclusion, we argue that these differences are related to the volume of cases which UK Screening Radiologists read in order to maintain skill level

Mammographic feature type and reader variability by occupation - an ROC study

Previous work has outlined that certain mammographic appearances feature more prominently in reader’s false negative responses on a self-assessment scheme. Bi-annually 600 breast-screening film-readers complete at least one round of the Personal Performance in Mammographic Screening (PERFORMS) self-assessment scheme in the UK. The main occupational groups in UK Breast Screening can be categorised thus, Radiologist, Technologists and Symptomatics. Previous work has shown that these groups can vary in their reading ‘style’ and accuracy on self-assessed cases. These groups could be said to contain individuals each with (arguably) pronounced differences in their real life reading experience, symptomatic readers routinely read a large number of cases with abnormal appearances and Technologists (specially trained to read films) do not have the same medical background as breast-screening Radiologists. We aimed to examine overall (national) and group (occupational) differences in terms of ROC analysis on those mammographic cases with different mammographic appearance (feature type). Several main feature types were identified namely; Well Defined Mass (WDM), Ill Defined Mass (IDM), Spiculate Mass (SPIC), Architectural Distortions (AD), Asymmetry (ASYM) and Calcification (CALC). Results are discussed in light of differences in real-life practice for each of the occupational groups and how this may impact on accuracy over certain mammographic appearances

Grid-enabled mammographic auditing and training system

Effective use of new technologies to support healthcare initiatives is important and current research is moving towards implementing secure grid-enabled healthcare provision. In the UK, a large-scale collaborative research project (GIMI: Generic Infrastructures for Medical Informatics), which is concerned with the development of a secure IT infrastructure to support very widespread medical research across the country, is underway. In the UK, there are some 109 breast screening centers and a growing number of individuals (circa 650) nationally performing approximately 1.5 million screening examinations per year. At the same, there is a serious, and ongoing, national workforce issue in screening which has seen a loss of consultant mammographers and a growth in specially trained technologists and other nonradiologists. Thus there is a need to offer effective and efficient mammographic training so as to maintain high levels of screening skills. Consequently, a grid based system has been proposed which has the benefit of offering very large volumes of training cases that the mammographers can access anytime and anywhere. A database, spread geographically across three university systems, of screening cases is used as a test set of known cases. The GIMI mammography training system first audits these cases to ensure that they are appropriately described and annotated. Subsequently, the cases are utilized for training in a grid-based system which has been developed. This paper briefly reviews the background to the project and then details the ongoing research. In conclusion, we discuss the contributions, limitations, and future plans of such a grid based approach