Jari Torniainen

Cognitive Collaboration Found in Cardiac Physiology: Study in Classroom Environment

It is known that periods of intense social interaction result in shared patterns in collaborators’ physiological signals. However, applied quantitative research on collaboration is hindered due to scarcity of objective metrics of teamwork effectiveness. Indeed, especially in the domain of productive, ecologically-valid activity such as programming, there is a lack of evidence for the most effective, affordable and reliable measures of collaboration quality. In this study we investigate synchrony in physiological signals between collaborating computer science students performing pair-programming exercises in a class room environment. We recorded electrocardiography over the course of a 60 minute programming session, using lightweight physiological sensors. We employ correlation of heart-rate variability features to study social psychophysiological compliance of the collaborating students. We found evident physiological compliance in collaborating dyads’ heart-rate variability signals. Furthermore, dyads’ self-reported workload was associated with the physiological compliance. Our results show viability of a novel approach to field measurement using lightweight devices in an uncontrolled environment, and suggest that self-reported collaboration quality can be assessed via physiological signals.

Feasibility of an electrodermal activity ring prototype as a research tool

Electrodermal activity is an indicator of sympathetic activation and a useful tool for investigating psychological and physiological arousal. Novel wearable skin conductivity sensors offer portable low-cost solutions for long-term monitoring. In this article we compare the similarity of signals between a prototype of the wearable Moodmetric EDA Ring and a laboratory-grade skin conductance sensor in a psychophysiological experiment. The similarity of the signals was estimated by calculating the cosine distance between phasic features extracted from decomposed signals. The similarity was on average 83.3% ± 16.4%. The compound error of the decomposition process was also investigated and no systematic bias was observed towards either device. We conclude that the prototype ring is a promising device for ecologically valid field studies.

Multitasking and Interruption Management in Control Room Operator Work During Simulated Accidents

Our everyday life is full of interruptions, which cause problems in different situations. Therefore, efficient management of interruptions is a natural part of our daily activity, and we humans are experts at managing task switching and interruptions. Efficient management of interruptions is required in many tasks and domains such as in health care, aviation, car driving and office work. This paper focusses on control room (CR) operator work in nuclear power plants. CR operators have to manage interruptions in various plant states, and sometimes interruptions cause problems in their work. This paper is divided into two major parts: the first part is a short literature review of effects of multitasking and interruptions in work settings; the second part presents some experimental results of multitasking and interruption management during simulated accidents. Some suggestions are given to improve interruption and multitasking management in safety-critical domains.

Near Infrared Spectroscopic Evaluation of Ligament and Tendon Biomechanical Properties

Knee ligaments and tendons are collagen-rich viscoelastic connective tissues that provide vital mechanical stabilization and support to the knee joint. Deterioration of ligaments has an adverse effect on the health of the knee and can eventually lead to ligament rupture and osteoarthritis. In this study, the feasibility of near infrared spectroscopy (NIRS) was, for the first time, tested for evaluation of ligament and tendon mechanical properties by performing measurements on bovine stifle joint ligament (N = 40) and patellar tendon (N = 10) samples. The mechanical properties of the samples were determined using a uniaxial tensile testing protocol. Partial least squares regression models were then developed to determine if morphological, viscoelastic, and quasi-static properties of the samples could be predicted from the NIR spectra. Best performance of NIRS in predicting mechanical properties was observed for toughness at yield point (median

Quantifying acute stress with heart rate variability (HRV) and electrodermal activity (EDA) in real world conditions

Q^{2}_{\rm{CV}}=0.54

A short review and primer on electromyography in human computer interaction applications.

QCV2=0.54, median normalized

Cardiac measures of nuclear power plant operator stress during simulated incident and accident scenarios

RMSE_{\rm{CV}}=6.1\%