Biofeedback in Virtual Reality applications and Gaming Bonie Rosario, Jr. Sebastian Osorio Tom Iancovici University of Massachusetts Lowell Intro to Biosensors Prof. Xingwei Wang
What is Biofeedback? Electroencephalogram NeuroPhone as EEG Application The Galvanic Skin Response Half-Life 2 as GSR Application Remaining Objectives Outline
Biofeedback = the technique of using monitoring devices to furnish information regarding an automatic bodily function, such as heart rate or blood pressure, in an attempt to gain some voluntary control over these functions[1]. What is Biofeedback?
EEG Biosensor
Electroencephalogram The electroencephalography is defined as a graphic representation of the potential difference between two different cerebral locations plotted over time[3]. EEG activity can be subdivided into various types of frequency rhythm bands. Research has indicated that different EEG frequency bands are associated with different mental states. The major five are alpha, theta, beta delta and gamma. EEG signals tend to have amplitude in the range of 2 V to 100 V
Emotive EPOC’s Hardware The Emotive EPOC EEG Headset samples the EEG signal at a rate of 120 Samples per Second (SPS) using an Analog-to-Digital Converter (ADC). It samples signals from 14 different electrodes and filters out artifacts, or noise, outside the bandwidth range of 0.2 – 45 Hz. It then is Emotiv EPOC headset Specification
Emotiv Software Development Kit (SDK) The detection suite provided for Emotive EPOC headset Developers Edition are: I. Expressive Suite: For user facial recognition II. Affective Suite: Monitors player emotional states in real-time. II. Cognitive Suite: Reads and interprets a player’s conscious thoughts and intent. Cognitive Suite
EEG Application NeuroPhone
EEG Application
GSR Biosensor
The galvanic skin response (GSR) is a simple method of capturing the autonomic nerve response as a parameter of the sweat gland function. Any stimulus capable of an arousal effect can evoke the response and the amplitude of the response is more dependent on the surprise effect of the stimulus than on the physical stimulus strength [2]. The Galvanic Skin Response
Stress Sweat glands are activated HRV Increased Heart Rate Low resistance pathway Apply small voltage to human skin to induce a current How GSR and HRV are Measured HRV= Heart Rate Variable GSR=Voltage/Current Also known as Instantaneous Skin Resistance
The heart rate and the galvanic skin response are very accurate manifestations of human reaction such as boredom, stress, and excitement. They are also very easy to measure using non-intrusive techniques. Different Commercially Available Products ccurres/13%20Electric%20Current%20&%20 Resistance/13.06%20galvanic%20skin%20re sponse.jpg hives/img/gsr2.jpg meditation.com/images/IOM- Technology.jpg
Biometric Application Vs. Gaming Application Issues Using GSR as Bio-feedback in a Gaming Application People react differently Need real time measurements
GSR/HRV Application: Half-Life 2
Increased speed = Increased HRV Increased volume = Increased GSR Screen shake = 3.8 Times average HRV X-ray vision = 0.5 – 0.7 average GSR Invisibility/Stealth = Less than 0.5 average GSR Red shader = 2 Times average HRV Black and white shader = Less than 0.8 average HRV Half-Life 2 Variables
Combining the biosensors Experiment by the University of Saskatchewan Saskatoon in Canada Deshpande Foundation and the Emotiv Neuro- Headset DEMO? Remaining Objectives
[1]"Biofeedback - Definition of Biofeedback by the Free Online Dictionary, Thesaurus and Encyclopedia." Dictionary, Encyclopedia and Thesaurus - The Free Dictionary. Web. 26 Feb [2]Tarvainen, M.P.; Karjalainen, P.A.; Koistinen, A.S.; Valkonen-Korhonen, M.V.;, "Principal component analysis of galvanic skin responses," Engineering in Medicine and Biology Society, Proceedings of the 22nd Annual International Conference of the IEEE, vol.4, no., pp vol.4, 2000 doi: /IEMBS URL: r= r=19495 [3] P Olejniczak. Neurophysiologic basis of eeg. Journal of clinical neurophysiology, 23 (3):186,