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Jul 29, 2008

Auditory and Spatial Navigation Imagery in Brain-Computer Interface using Optimized Wavelets

Auditory and Spatial Navigation Imagery in Brain-Computer Interface using Optimized Wavelets.

J Neurosci Methods. 2008 Jul 6;

Authors: Cabrera AF, Dremstrup K

Features extracted with optimized wavelets were compared with standard methods for a Brain-Computer Interface driven by non-motor imagery tasks. Two non-motor imagery tasks were used, Auditory Imagery of a familiar tune and Spatial Navigation Imagery through a familiar environment. The aims of this study were to evaluate which method extracts features that could be best differentiated and determine which channels are best suited for classification. EEG activity from 18 electrodes over the temporal and parietal lobes of nineteen healthy subjects was recorded. The features used were autoregressive and reflection coefficients extracted using autoregressive modeling with several model orders and marginals of the wavelet spaces generated by the Discrete Wavelet Transform (DWT). An optimization algorithm with 4 and 6 taps filters and mother wavelets from the Daubechies family were used. The classification was performed for each single channel and for all possible combination of two channels using a Bayesian Classifier. The best classification results were found using the marginals of the Optimized DWT spaces for filters with 6 taps in a 2 channels classification basis. Classification using 2 channels was found to be significantly better than using 1 channel (p<<0.01). The marginals of the optimized DWT using 6 taps filters showed to be significantly better than the marginals of the Daubechies family and autoregressive coefficients. The influence of the combination of number of channels and feature extraction method over the classification results was not significant (p=0.97).

Jul 28, 2008

Does erotic stimulus presentation design affect brain activation patterns?

Does erotic stimulus presentation design affect brain activation patterns? Event-related vs. blocked fMRI designs.

Behav Brain Funct. 2008 Jul 22;4(1):30

Authors: Buehler M, Vollstaedt-Klein S, Klemen J, Smolka MN

ABSTRACT: BACKGROUND: Existing brain imaging studies, investigating sexual arousal via the presentation of erotic pictures or film excerpts, have mainly used blocked designs with long stimulus presentation times. METHODS: To clarify how experimental functional magnetic resonance imaging (fMRI) design affects stimulus-induced brain activity, we compared brief event-related presentation of erotic vs. neutral stimuli with blocked presentation in 10 male volunteers. RESULTS: Brain activation differed depending on design type in only 10% of the voxels showing task related brain activity. Differences between blocked and event-related stimulus presentation were found in occipitotemporal and temporal regions (Brodmann Area (BA) 19, 37, 48), parietal areas (BA 7, 40) and areas in the frontal lobe (BA 6, 44). CONCLUSIONS: Our results suggest that event-related designs might be a potential alternative when the core interest is the detection of networks associated with immediate processing of erotic stimuli. Additionally, blocked, compared to event-related, stimulus presentation allows the emergence and detection of non-specific secondary processes, such as sustained attention, motor imagery and inhibition of sexual arousal.

Development and preliminary evaluation of a prototype audiovisual biofeedback device

Development and preliminary evaluation of a prototype audiovisual biofeedback device incorporating a patient-specific guiding waveform.

Phys Med Biol. 2008 May 12;53(11):N197-N208

Authors: Venkat RB, Sawant A, Suh Y, George R, Keall PJ

The aim of this research was to investigate the effectiveness of a novel audio-visual biofeedback respiratory training tool to reduce respiratory irregularity. The audiovisual biofeedback system acquires sample respiratory waveforms of a particular patient and computes a patient-specific waveform to guide the patient's subsequent breathing. Two visual feedback models with different displays and cognitive loads were investigated: a bar model and a wave model. The audio instructions were ascending/descending musical tones played at inhale and exhale respectively to assist in maintaining the breathing period. Free-breathing, bar model and wave model training was performed on ten volunteers for 5 min for three repeat sessions. A total of 90 respiratory waveforms were acquired. It was found that the bar model was superior to free breathing with overall rms displacement variations of 0.10 and 0.16 cm, respectively, and rms period variations of 0.77 and 0.33 s, respectively. The wave model was superior to the bar model and free breathing for all volunteers, with an overall rms displacement of 0.08 cm and rms periods of 0.2 s. The reduction in the displacement and period variations for the bar model compared with free breathing was statistically significant (p = 0.005 and 0.002, respectively); the wave model was significantly better than the bar model (p = 0.006 and 0.005, respectively). Audiovisual biofeedback with a patient-specific guiding waveform significantly reduces variations in breathing. The wave model approach reduces cycle-to-cycle variations in displacement by greater than 50% and variations in period by over 70% compared with free breathing. The planned application of this device is anatomic and functional imaging procedures and radiation therapy delivery.

Energetic assessment of trunk postural modifications induced by a wearable audio-biofeedback system

Energetic assessment of trunk postural modifications induced by a wearable audio-biofeedback system.

Med Eng Phys.
2008 Jul 2;

Authors: Giansanti D, Dozza M, Chiari L, Maccioni G, Cappello A

This paper investigates the trunk postural modifications induced by a wearable device which assesses the trunk sway and provides biofeedback information through sonification of trunk kinematics. The device is based on an inertial wearable sensing unit including three mono-axial accelerometers and three rate gyroscopes embedded and mounted orthogonally. The biofeedback device was tested on nine healthy subjects during quiet stance in different conditions of sensory limitation eyes closed on solid surface, eyes open on foam cushion surface, eyes closed on foam cushion surface. Five trials were performed for each condition; the order of the trials was randomized. The results reported in this paper show how subjects reduced their rotational kinetic energy by using the biofeedback information and how this reduction was related to the limitation of sensory information.

Jul 23, 2008

Web GIS in practice VI: a demo "playlist" of geo-mashups for public health neogeographers

Web GIS in practice VI: a demo "playlist" of geo-mashups for public health neogeographers.

Int J Health Geogr. 2008 Jul 18;7(1):38

Authors: Kamel Boulos MN, Scotch M, Cheung KH, Burden D

ABSTRACT: 'Mashup' was originally used to describe the mixing together of musical tracks to create a new piece of music. The term now refers to Web sites or services that weave data from different sources into a new data source or service. Using a musical metaphor that builds on the origin of the word 'mashup', this paper presents a demonstration "playlist" of four geo-mashup vignettes that make use of a range of Web 2.0, Semantic Web, and 3-D Internet methods, with outputs/end-user interfaces spanning the flat Web (two-dimensional -- 2-D maps), a three-dimensional -- 3-D mirror world (Google Earth) and a 3-D virtual world (Second Life (R)). The four geo-mashup "songs" in this "playlist" are: 'Web 2.0 and GIS (Geographic Information Systems) for infectious disease surveillance', 'Web 2.0 and GIS for molecular epidemiology', 'Semantic Web for GIS mashup', and 'From Yahoo! Pipes to 3-D, avatar-inhabited geo-mashups'. It is hoped that this showcase of examples and ideas, and the pointers we are providing to the many online tools that are freely available today for creating, sharing and reusing geo-mashups with minimal or no coding, will ultimately spark the imagination of many public health practitioners and stimulate them to start exploring the use of these methods and tools in their day-to-day practice. The paper also discusses how today's Web is rapidly evolving into a much more intensely immersive, mixed-reality and ubiquitous socio-experiential Metaverse that is heavily interconnected through various kinds of user-created mashups.

Jul 22, 2008

The effects of self-involvement on attention, arousal, and facial expression during social interaction with virtual others

The effects of self-involvement on attention, arousal, and facial expression during social interaction with virtual others: A psychophysiological study.

Soc Neurosci. 2006;1(3-4):184-95

Authors: Mojzisch A, Schilbach L, Helmert JR, Pannasch S, Velichkovsky BM, Vogeley K

Social neuroscience has shed light on the underpinnings of understanding other minds. The current study investigated the effect of self-involvement during social interaction on attention, arousal, and facial expression. Specifically, we sought to disentangle the effect of being personally addressed from the effect of decoding the meaning of another person's facial expression. To this end, eye movements, pupil size, and facial electromyographic (EMG) activity were recorded while participants observed virtual characters gazing at them or looking at someone else. In dynamic animations, the virtual characters then displayed either socially relevant facial expressions (similar to those used in everyday life situations to establish interpersonal contact) or arbitrary facial movements. The results show that attention allocation, as assessed by eye-tracking measurements, was specifically related to self-involvement regardless of the social meaning being conveyed. Arousal, as measured by pupil size, was primarily related to perceiving the virtual character's gender. In contrast, facial EMG activity was determined by the perception of socially relevant facial expressions irrespective of whom these were directed towards.

Robot butler

From Smart Mobs 
 

Care-O-bot 3 serving a drink

(Credit: Fraunhofer IPA
 
German researchers from the Fraunhofer Institute have introduced their third generation of household robots, the Care-O-Bot 3. The robot has has a flexible arm with seven degrees of freedom and a hand with three fingers. This allows it to pick up bottles, cups and similar objects and to operate machines.

Here are the major functionalities of Care-O-bot 3:

 

  • Omnidirectional Navigation: Care-O-bot 3 has an omnidirectional platform, with four steered and driven wheels. This kinematic system enables the robot to move in any desired direction and therefore also safely to negotiate narrow passages.
  • Safe Manipulation: Care-O-bot 3 is equipped with a highly flexible, commercial arm with seven degrees of freedom as well as with a three-finger hand. This makes it capable of gripping and operating a large number of different everyday objects.
  • 3D Environment Detection: A multiplicity of sensors enables Care-O-bot 3 to detect the environment in which it is operating. These range from stereo vision colour cameras and laser scanners to a 3D depth-image camera.
  • Software Architecture/Middleware: Several interlinked computers are used to evaluate and control the sensors and actuators inside the robot. The system resources are coordinated and managed by a specially developed middleware which controls communications between the individual processes and which reacts appropriately in the event of a malfunction.
  • Human-Machine Interaction: The primary interface between Care-Obot 3 and the user consists of a tray attached to the front of the robot, which carries objects for exchange between the human and the robot. The tray includes a touch screen and retracts automatically when not in use. A laser projector on the gripper also enables the robot to project information onto objects.
 
 
 

14:25 Posted in AI & robotics | Permalink | Comments (0)

Web Trend Map 2008

Have a look at the Web Trend Map 2008, by Information Architects

The map is based on the Tokyo underground

Web Trend Map 3 2008 Information Architects Japan

Larger formats are available:

  1. Clickable Startpage with daily updated iA surf tips
  2. Big, A3 PDF (8MB, printable)
  3. 1600 x 1024 Wallpaper
  4. 1440 x 900 Wallpaper

 

 

Techniques and devices to restore cognition

Techniques and devices to restore cognition.

Behav Brain Res. 2008 Oct 10;192(2):149-65

Authors: Serruya MD, Kahana MJ

Executive planning, the ability to direct and sustain attention, language and several types of memory may be compromised by conditions such as stroke, traumatic brain injury, cancer, autism, cerebral palsy and Alzheimer's disease. No medical devices are currently available to help restore these cognitive functions. Recent findings about the neurophysiology of these conditions in humans coupled with progress in engineering devices to treat refractory neurological conditions imply that the time has arrived to consider the design and evaluation of a new class of devices. Like their neuromotor counterparts, neurocognitive prostheses might sense or modulate neural function in a non-invasive manner or by means of implanted electrodes. In order to paint a vision for future device development, it is essential to first review what can be achieved using behavioral and external modulatory techniques. While non-invasive approaches might strengthen a patient's remaining intact cognitive abilities, neurocognitive prosthetics comprised of direct brain-computer interfaces could in theory physically reconstitute and augment the substrate of cognition itself.

Jul 18, 2008

Effects of mental imagery styles on shoulder and hip rotations during preparation of pirouettes

Effects of mental imagery styles on shoulder and hip rotations during preparation of pirouettes.

J Mot Behav. 2008 Jul;40(4):281-90

Authors: Golomer E, Bouillette A, Mertz C, Keller J

To analyze individual behavior in spatial navigation especially for pirouette preparations (complete whole-body rotations), the authors studied horizontal shoulder-hip interactions under 2 constraints: postural (right and left supporting legs [SL]) and spatial (clockwise [CW] and counterclockwise [CCW]). They performed kinematic analysis at the start and end of the shoulder-hip horizontal rotations (run-up) with regard to imagery of motor actions. On the basis of the Vividness of Movement Imagery Questionnaire, they classified 8 female expert ballet dancers and 7 untrained female participants according to their movement imagery style (kinesthetic and visual). At the run-up's end, the shoulders initiated the turn independently of SL but differently depending on training: CW for dancers and CCW for untrained participants (their commonly used direction). Kinesthetic and mixed imagery styles prevailed in dancers, whereas simply a mixed style appeared among untrained participants. Thus, dance training enhances the imagery of kinesthetic sensation and influences the choice of spatial direction, facilitating the body-space interaction.

Jul 16, 2008

Einstein's Brain Game

Via MobileGames 

The Walt Disney Internet Group has released the "Einstein's Brain Game".


The game proposes 20 brain training exercises covering Einstein’s theories of relativity and ideas about the solar system. It features 4 categories - maths, memory, logic and visual coordination, as well as a bonus Sudoku puzzle game, to give the brain a thorough work-out.

 

Jul 10, 2008

Virtual reality exposure therapy for active duty soldiers

Virtual reality exposure therapy for active duty soldiers.

J Clin Psychol. 2008 Jul 8;

Authors: Reger GM, Gahm GA

Virtual reality exposure (VRE) therapy is a promising treatment for a variety of anxiety disorders and has recently been extended to the treatment of posttraumatic stress disorder (PTSD). In this article, the authors briefly review the rationale for VRE and its key processes. They illustrate the treatment with an active-duty Army soldier diagnosed with combat-related PTSD. Six sessions of VRE were provided using an immersive simulation of a military convoy in Iraq. Self-reported PTSD symptoms and psychological distress were reduced at posttreatment relative to pretreatment reports, as assessed by the PTSD Checklist-Military Version and the Behavior and Symptom Identification Scale-24. The case outcomes parallel those reported in the research with other disorders and suggest the applicability of VRE in treating active duty soldiers with combat-related PTSD. (c) 2008 Wiley Periodicals, Inc. J Clin Psychol: In Session 64:1-7, 2008.

Jul 09, 2008

Usefulness of mindfulness-based cognitive therapy for treating insomnia in patients with anxiety disorders: a pilot study

Usefulness of mindfulness-based cognitive therapy for treating insomnia in patients with anxiety disorders: a pilot study.

J Nerv Ment Dis. 2008 Jun;196(6):501-3

Authors: Yook K, Lee SH, Ryu M, Kim KH, Choi TK, Suh SY, Kim YW, Kim B, Kim MY, Kim MJ

The objective of this study was to examine the usefulness of a mindfulness-based cognitive therapy (MBCT) for treating insomnia symptoms in patients with anxiety disorder. Nineteen patients with anxiety disorder were assigned to an 8-week MBCT clinical trial. Participants showed significant improvement in Pittsburgh Sleep Quality Index (Z = -3.46, p = 0.00), Penn State Worry Questionnaire (Z = -3.83, p = 0.00), Ruminative Response Scale (Z = -3.83, p = 0.00), Hamilton Anxiety Rating Scale (Z = -3.73, p = 0.00), and Hamilton Depression Rating Scale scores (Z = -3.06, p = 0.00) at the end of the 8-week program as compared with baseline. Multiple regression analysis showed that baseline Penn State Worry Questionnaire scores were associated with baseline Pittsburgh Sleep Quality Index scores. These findings suggest that MBCT can be effective at relieving insomnia symptoms by reducing worry associated sleep disturbances in patients with anxiety disorder. However, well-designed, randomized, controlled trials are needed to confirm our findings.

Google Lively launched

Internet giant Google has unveiled its response to Second Life, an online 3D world called Lively. To play with Lively, users need to download and install a client (Windows-only for now, but a Mac OS x client is planned) and then they can use their web browser (Firefox or Internet Explorer) to enter the virtual world.

Once registered, users can set up their own spaces, change the form and clothing of their avatars, and communicate with other players via chat or gestures.  

Lively is less immersive than second life and easier to use (with a drag-and-drop interface), but it is not programmable: users can only select items from the catalog provided by Google. Further, Lively has does not have money for now, though the company is considering the introduction of a currency. 


Click to enter A place for all the cowboys.

Using mental practice in stroke rehabilitation: a framework

Using mental practice in stroke rehabilitation: a framework.

Clin Rehabil. 2008 Jul;22(7):579-91

Authors: Braun S, Kleynen M, Schols J, Schack T, Beurskens A, Wade D

Introduction: Motor imagery and mental practice are getting increased attention in neurological rehabilitation. Several different mental practice intervention protocols have been used in studies on its effect on recovery in stroke rehabilitation. The content of the intervention protocols itself is rarely discussed or questioned.Objective: To give a practical framework of how mental practice could be integrated into therapy, drawing on available evidence and theory. The aim of the treatment programme described is to enhance both the patient's physical performance and their empowerment and self-determination.The framework: Based on evidence from sports rehabilitation and our own experiences the framework will eventually be evaluated in a randomized controlled trial. Five steps are described to teach and upgrade the patient's imagery technique: (1) assess mental capacity to learn imagery technique; (2) establish the nature of mental practice; (3) teach imagery technique; (4) embed and monitor imagery technique; (5) develop self-generated treatments. The description is not, however, a recipe that should be followed precisely. It leaves enough room to tailor the mental practice intervention to the specific individual possibilities, skills and needs of the patient in accordance with evidence-based practice.Discussion: Different aspects of the described protocol are discussed and compared with experiences from sports and evidence available in rehabilitation.

Brain motor system function in a patient with complete spinal cord injury

Brain motor system function in a patient with complete spinal cord injury following extensive brain-computer interface training.

Exp Brain Res. 2008 Jul 1;

Authors: Enzinger C, Ropele S, Fazekas F, Loitfelder M, Gorani F, Seifert T, Reiter G, Neuper C, Pfurtscheller G, Müller-Putz G

Although several features of brain motor function appear to be preserved even in chronic complete SCI, previous functional MRI (fMRI) studies have also identified significant derangements such as a strongly reduced volume of activation, a poor modulation of function and abnormal activation patterns. It might be speculated that extensive motor imagery training may serve to prevent such abnormalities. We here report on a unique patient with a complete traumatic SCI below C5 who learned to elicit electroencephalographic signals beta-bursts in the midline region upon imagination of foot movements. This enabled him to use a neuroprosthesis and to "walk from thought" in a virtual environment via a brain-computer interface (BCI). We here used fMRI at 3T during imagined hand and foot movements to investigate the effects of motor imagery via persistent BCI training over 8 years on brain motor function and compared these findings to a group of five untrained healthy age-matched volunteers during executed and imagined movements. We observed robust primary sensorimotor cortex (SMC) activity in expected somatotopy in the tetraplegic patient upon movement imagination while such activation was absent in healthy untrained controls. Sensorimotor network activation with motor imagery in the patient (including SMC contralateral to and the cerebellum ipsilateral to the imagined side of movement as well as supplementary motor areas) was very similar to the pattern observed with actual movement in the controls. We interpret our findings as evidence that BCI training as a conduit of motor imagery training may assist in maintaining access to SMC in largely preserved somatopy despite complete deafferentation.

Jul 08, 2008

Virtual reality and persecutory delusions: Safety and feasibility

Virtual reality and persecutory delusions: Safety and feasibility.

Schizophr Res. 2008 Jun 20;

Authors: Fornells-Ambrojo M, Barker C, Swapp D, Slater M, Antley A, Freeman D

OBJECTIVE: Virtual reality (VR) has begun to be used to research the key psychotic symptom of paranoia. The initial studies have been with non-clinical individuals and individuals at high risk of psychosis. The next step is to develop the technology for the understanding and treatment of clinical delusions. Therefore the present study investigated the acceptability and safety of using VR with individuals with current persecutory delusions. Further, it set out to determine whether patients feel immersed in a VR social environment and, consequently, experience paranoid thoughts. METHOD: Twenty individuals with persecutory delusions and twenty non-clinical individuals spent 4 min in a VR underground train containing neutral characters. Levels of simulator sickness, distress, sense of presence, and persecutory ideation about the computer characters were measured. A one-week follow-up was conducted to check longer-term side effects. RESULTS: The VR experience did not raise levels of anxiety or symptoms of simulator sickness. No side effects were reported at the follow-up. There was a considerable degree of presence in the VR scenario for all participants. A high proportion of the persecutory delusions group (65%) had persecutory thinking about the computer characters, although this rate was not significantly higher than the non-clinical group. CONCLUSIONS: The study indicates that brief experiences in VR are safe and acceptable to people with psychosis. Further, patients with paranoia can feel engaged in VR scenes and experience persecutory thoughts. Exposure to social situations using VR has the potential to be incorporated into cognitive behavioural interventions for paranoia.

New BCI system for gaming applications

Emotiv Systems has developed a new brain computer interface headset for video games and other uses. Emotiv’s president Tan Le claims that the headset will be on sale around the end of this year ($299).