Validating a new clinical subtyping scheme for delirium with electronic motion analysis

The usefulness of motor subtypes of delirium is unclear due to inconsistency in sub-typing methods and a lack of validation with objective measures of activity. The activity of 40 patients was measured with 24 h accelerometry monitoring. Patients with Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV) delirium (n = 30) were allocated into hyperactive, hypoactive and mixed motor subtypes. Delirium subtypes differed in relation to overall amount of activity, including movement in both sagittal and transverse planes. Differences were greater in the daytime and during the early evening ‘sundowning’ period. Frequency of postural changes was the most discriminating measure examined. Clinical subtypes of delirium defined by observed motor behaviour on the ward differ in electronically measured activity levels.

Movement time for motion-impaired users assisted by force-feedback: effects of movement amplitude, target width and gravity well width

This paper presents a study investigating how the performance of motion-impaired computer users in point and click tasks varies with target distance (A), target width (W), and force-feedback gravity well width (GWW). Six motion-impaired users performed point and click tasks across a range of values for A, W, and GWW. Times were observed to increase with A, and to decrease with W. Times also improved with GWW, and, with the addition of a gravity well, a greater improvement was observed for smaller targets than for bigger ones. It was found that Fitts Law gave a good description of behaviour for each value of GWW, and that gravity wells reduced the effect of task difficulty on performance. A model based on Fitts Law is proposed, which incorporates the effect of GWW on movement time. The model accounts for 88.8% of the variance in the observed data.

Visual motion interferes with lexical decision on motion words

Embodied theories of cognition propose that neural substrates used in experiencing the referent of a word, for example perceiving upward motion, should be engaged in weaker form when that word, for example ‘rise’, is comprehended. Motivated by the finding that the perception of irrelevant background motion at near-threshold, but not supra-threshold, levels interferes with task execution, we assessed whether interference from near-threshold background motion was modulated by its congruence with the meaning of words (semantic content) when participants completed a lexical decision task (deciding if a string of letters is a real word or not). Reaction times for motion words, such as ‘rise’ or ‘fall’, were slower when the direction of visual motion and the ‘motion’ of the word were incongruent — but only when the visual motion was at nearthreshold levels. When motion was supra-threshold, the distribution of error rates, not reaction times, implicated low-level motion processing in the semantic processing of motion words. As the perception of near-threshold signals is not likely to be influenced by strategies, our results support a close contact between semantic information and perceptual systems.

Motion detection and motion verbs: language affects low-level visual perception

Recent theories propose that semantic representation and sensorimotor processing have a common substrate via simulation. We tested the prediction that comprehension interacts with perception, using a standard psychophysics methodology.While passively listening to verbs that referred to upward or downward motion, and to control verbs that did not refer to motion, 20 subjects performed a motion-detection task, indicating whether or not they saw motion in visual stimuli containing threshold levels of coherent vertical motion. A signal detection analysis revealed that when verbs were directionally incongruent with the motion signal, perceptual sensitivity was impaired. Word comprehension also affected decision criteria and reaction times, but in different ways. The results are discussed with reference to existing explanations of embodied processing and the potential of psychophysical methods for assessing interactions between language and perception.

Counting Her Dresses and other plays

Counting Her Dresses and other plays, devised by Lib Taylor, is a short, mixed-media, promenade performance based on theatre writings by Gertrude Stein. Gertrude Stein was an American writer who lived in Paris for most of her adult life and was a significant figure in the development of early twentieth century modernism. She was an artists’ patron and one of the first collectors of paintings by Picasso, Matisse, Cezanne and others. She wrote novels, short stories, poetry and criticism, as well as a number of very short ‘plays’ and opera libretti. Even though her plays are very rarely performed they have been very influential in the development of avant-garde theatre. The performance juxtaposes a soundcape of voices, live performance, an ‘exhibition’ of paintings and mediated images projected onto and across the space to evoke Stein’s sense of theatre as a place of experience and emotion, not as a place of story and action. The performance comprises five theatre fragments which have been combined in a collage that alludes to the experimental art that Stein promoted.

Realism and politics in alienated space: Trevor Griffiths's plays of the 1970s in the television studio

The television studio play is often perceived as a somewhat compromised, problematic mode in which spatial and technological constraints inhibit the signifying and aesthetic capacity of dramatic texts. Leah Panos examines the function of the studio in the 1970s television dramas of socialist playwright Trevor Griffiths, and argues that the established verbal and visual conventions of the studio play, in its confined and ‘alienated’ space, connect with and reinforce various aspects of Griffiths's particular approach and agenda. As well as suggesting ways in which the idealist, theoretical focus of the intellectual New Left is reflexively replicated within the studio, Panos explores how the ‘intimate’ visual language of the television studio allows Griffiths to create a ‘humanized’ Marxist discourse through which he examines dialectically his dramatic characters' experiences, ideas, morality, and political objectives. Leah Panos recently completed her doctoral thesis, ‘Dramatizing New Left Contradictions: Television Texts of Ken Loach, Jim Allen, and Trevor Griffiths’, at the University of Reading and is now a Postdoctoral Researcher on the AHRC funded project, ‘Spaces of Television: Production, Site and Style’, which runs from July 2010 to March 2014.

Motion estimation through approximated densities

Many techniques are currently used for motion estimation. In the block-based approaches the most common procedure applied is the block-matching based on various algorithms. To refine the motion estimates resulting from the full search or any coarse search algorithm, one can find few applications of Kalman filtering, mainly in the intraframe scheme. The Kalman filtering technique applicability for block-based motion estimation is rather limited due to discontinuities in the dynamic behaviour of the motion vectors. Therefore, we propose an application of the concept of the filtering by approximated densities (FAD). The FAD, originally introduced to alleviate limitations due to conventional Kalman modelling, is applied to interframe block-motion estimation. This application uses a simple form of FAD involving statistical characteristics of multi-modal distributions up to second order.