Combining brain-computer interfaces and assistive technologies: state-of-the-art and challenges

In recent years, new research has brought the field of EEG-based Brain-Computer Interfacing (BCI) out of its infancy and into a phase of relative maturity through many demonstrated prototypes such as brain-controlled wheelchairs, keyboards, and computer games. With this proof-of-concept phase in the past, the time is now ripe to focus on the development of practical BCI technologies that can be brought out of the lab and into real-world applications. In particular, we focus on the prospect of improving the lives of countless disabled individuals through a combination of BCI technology with existing assistive technologies (AT). In pursuit of more practical BCIs for use outside of the lab, in this paper, we identify four application areas where disabled individuals could greatly benefit from advancements in BCI technology, namely,“Communication and Control”, “Motor Substitution”, “Entertainment”, and “Motor Recovery”. We review the current state of the art and possible future developments, while discussing the main research issues in these four areas. In particular, we expect the most progress in the development of technologies such as hybrid BCI architectures, user-machine adaptation algorithms, the exploitation of users’ mental states for BCI reliability and confidence measures, the incorporation of principles in human-computer interaction (HCI) to improve BCI usability, and the development of novel BCI technology including better EEG devices

Spatial context in the early visual system

Important visual objects in our everyday life, such as fellow people, passing cars or birds perhaps, are not point-like structures but often occupy considerable amounts of the visual field. However, each photoreceptor in our eyes samples just a tiny portion of the visual field and somehow the visual system should integrate these local signals. This process takes place mainly in the visual cortex and, while higher-order visual areas play an important role in perception of extended structures, it is now well established that visual neurons at the first cortical steps of seeing integrate broad spatial context into their responses. The main purpose of this thesis was to provide detailed information concerning the spatial structure of the mechanisms that underlie integration of spatial context in the early visual system. The opening study of this thesis showed that the antagonistic Gaussians structure that has been used for modeling context integration in single visual neurons provides a relatively accurate description of the process also in the human visual system. The first study introduced a novel method for connecting perceptual and neuroimaging measurements and this method was applied in the second study of this thesis. The second study showed that the human visual system integrates spatial context in terms of its visual field size instead of the size of its cortical representation. The third study showed that context is integrated over an unexpectedly large region of the visual field and that spatially distant context may sometimes increase the contrast response of the visual system. The closing study showed that orientation specificity of the integration of spatial context depends on distance both in single neurons in the macaque primary visual cortex and in human perception. The knowledge acquired in this thesis will be generally useful in applications that require understanding of the human visual system.Arkielämän kannalta tärkeät visuaaliset objektit kuten ihmiset, ohikiitävät autot ja kenties kissat, ovat harvoin pistemäisiä, mutta sen sijaan voivat peittää laajankin alueen näkökentästä. Näköaistinsolut prosessoivat kuvainformaatiota erittäin pieneltä näkökentän alueelta ja näköjärjestelmän tulee jollain tavoin yhdistää nämä paikalliset signaalit. Vaikka näköaivokuoren myöhäisten alueiden merkitys spatiaalisesti laajojen objektien havaitsemisessa onkin merkittävä, nykytietämyksen valossa on kiistatonta että myös varhaisten näköaivokuorten hermosolut integroivat spatiaalista kontekstia laajalta näkökentän alueelta. Tässä väitöskirjassa tutkitaan konteksti-integraation taustalla olevien mekanismien spatiaalista rakennetta varhaisessa näköjärjestelmässä. Väitöskirjan ensimmäisessä osatyössä osoitettiin että konteksti-integraatiota yksittäisissä hermosoluissa kuvaavat kahden antagonistisen Gaussilaisen mallit ovat melko hyviä kuvauksia konteksti-integraatiomekanismien spatiaalisesta rakenteesta myös ihmisen näköjärjestelmässä. Ensimmäisessä osatyössä kehitettiin menetelmä joka mahdollistaa havainto- ja aivokuvantamismittausten uudenlaisen yhdistämisen. Tätä menetelmää sovellettiin toisessa osatyössä, jonka päätulos oli konteksti-integraation riippuvuus ärsykkeen koosta näkökentässä sen sijaan että se olisi sidoksissa ärsykkeen edustuksen kokoon aivokuorella. Kolmannessa osatyössä osoitettiin, että kontekstia integroidaan huomattavan laajalta alueelta ja että spatiaalisesti etäinen konteksti saattaa toisinaan vahvistaa näköjärjestelmän kontrastivastetta. Neljäs tutkimus osoitti, että konteksti-integraation valikoivuus orientaatiolle riippuu etäisyydestä niin ihmisen näköhavainnoissa kuin makaki-apinan ensimmäisen näköaivokuoren soluissakin. Tämän väitöskirjan tuloksia voidaan hyödyntää sovelluksissa joissa tarvitaan tietoa ihmisen näköjärjestelmän toiminnasta

Affective Brain-Computer Interfaces Neuroscientific Approaches to Affect Detection

The brain is involved in the registration, evaluation, and representation of emotional events, and in the subsequent planning and execution of adequate actions. Novel interface technologies – so-called affective brain-computer interfaces (aBCI) - can use this rich neural information, occurring in response to affective stimulation, for the detection of the affective state of the user. This chapter gives an overview of the promises and challenges that arise from the possibility of neurophysiology-based affect detection, with a special focus on electrophysiological signals. After outlining the potential of aBCI relative to other sensing modalities, the reader is introduced to the neurophysiological and neurotechnological background of this interface technology. Potential application scenarios are situated in a general framework of brain-computer interfaces. Finally, the main scientific and technological challenges that have to be solved on the way toward reliable affective brain-computer interfaces are discussed

Mental Associations and Music Therapy: Including the History of Associationism and the Neurology of Associations

Associations are formed in our minds based upon three elements: sensory experience, emotions, and memories. These associations, unique to each individual, dictate thoughts, beliefs, behaviors, and actions. Some are necessary and supportive, while others can be maladaptive. Established associations can be changed, and new associations can be formed, to align with a client’s goals. The literature presents a strong history of associationism, as well as a body of research that demonstrates the neurological processes of how mental associations are formed. There are also studies showing how music activates the brain. However, there is a lack of research which draws direct correlations between the regions of the brain involved in forming associations and the regions of the brain activated during music engagement, resulting in a missed opportunity to use music, especially music therapy, in the context of working with a client’s associations. The history of associationism, the neurology of associations, and the brain’s response to music introduced a strong comparison between brain regions involved in forming associations and those activated while exposed to music, supporting the idea that music therapy can be a strong tool to use in conjunction with other therapeutic models to enhance the efficacy of creating new or shifting current mental associations to support a client’s therapeutic goals

Circadian Rhythm and Vigorous Activity: Do They Make a Difference in Executive Function?

PL 107-110, the No Child Left Behind Act of 2001, a federally mandated accountability system based on standards, attendance, and dropout rates has forced educational leaders to explore new avenues of student improvement. Research suggests that all three factors are impacted by scheduling preferences that are relative to time of day. The aim of this study was to extend evidence of executive function as it is impacted by time of day and diurnal preference when exposed to vigorous exercise conditions. Data were collected from a sample that included 100 sixth graders (60 females and 40 males) during the spring semester 2011 from two southern parishes in Louisiana. Diurnal preferences were identified using the Morningness/Eveningness Scale for Children (Carskadon, Vieira, & Acebo, 1993). A pre-test and post-test of the Wisconsin Card Sorting Test- 64 (WCST-64) were performed during preferred and non-preferred times to indicate executive function changes. The post-test was performed after completion of the Multiple Level 20 meter shuttle run to simulate vigorous exercise conditions. A two-way ANOVA analysis with repeated measures on the WCST-64 did not yield any significant findings to support time of day or diurnal preference impact on executive function when exposed to vigorous exercise conditions

Vigilance of Certified Registered Nurse Anesthetists

Vigilance of certified registered nurse anesthetists (CRNAs) is an integral component of the care they provide patients under general anesthetic. the practice of CRNas is important as the official seal of the American Association of Nurse Anesthetists (AANA). on the seal, Morpheus, the god of dreams, is shown holding the Lamp of Learning, by the light of which he keeps vigil (Hirter & Van Nest, 1995). as the patients remain unconscious under general anesthesia, CRNas remain the patients\u27 eyes and ears remains responsive to their needs. the CRNa must remain attentive to the patient\u27s needs by continuously monitoring the patient in the operating room and constantly communicating with the operating room staff. Complete focus must be maintained to avoid any mishaps or adverse events. in essence, CRNas must remain focused and vigilant when caring for their patients. the importance of vigilance is essential and undeniable for optimal patient outcomes, but the process has yet to be defined and understood. Fourteen CRNas participated in phone interviews in this study. CRNas practicing in both hospital and ambulatory settings were included. Through data analysis, using constant comparison, a model emerged that explained vigilance in the CRNa process. the core category was Using Senses, and the model had seven subcategories. the categories below reflected stages in the process model. the process begins with the CRNA\u27s care of the patient (Being Alert). This is when the CRNa assumes care of the patient, maintains a high level of alertness, and does not get mentally fatigued. Being alert allows the CRNa to be ready to care for their patients. When CRNas are alert, they are attentive and engaged (Being Attentive and Engaged) in watching over their patients. This allows the CRNa to be constantly aware and pay attention to their patients. Being attentive and engaged allows the CRNa to be focused (Focusing) on every aspect of patient care. Unfortunately, the operating room is a dynamic environment, where distractions, such as music, conversation, and technology can distract clinicians from being engaged in the care of their patients. These distractions can, but do not always, occur. When they do occur, the CRNa redirects their attention and begins to focus, which allows CRNas to use their senses to look, listen, and feel (Looking, Listening, and Touching). Using the senses of looking, listening, and feeling, the CRNa can pick up on events or look for cues that can help continue or improve care by anticipating changes at random intervals during the case. by using their senses and picking up on cues, the CRNa knows what is going on with the patient (Know What Is Happening). the findings of this study have implications for nurse administrators. This theory will be informative and helpful for hospital administrators, as they may want to implement a policy similar to that which the aviation industry developed for pilots reporting for duty. in regards to nursing research, the Institute of Medicine ([IOM], 2003) has used the phenomena of vigilance and surveillance interchangeably, but the processes are not interchangeable. There is a distinction between these two concepts. This study provides a link between the two phenomena. Vigilance is a link to the process of surveillance and studying it will help the researcher expound upon the previous surveillance research in nursing

Functional NIRS to detect covert consciousness in neurocritical patients

Objective This pilot study assesses the feasibility to detect covert consciousness in clinically unresponsive patients by means of functional near infrared spectroscopy (fNIRS) in a real intensive care unit setting. We aimed to verify if the hemodynamic response to familiar music measured with fNIRS varies according to the level consciousness of the patients. Methods 22 neurocritical patients and 6 healthy controls were included. The experiment consisted in 3 subsequent blocks including a first resting state recording, a period of music playback and a second resting state recording. fNIRS measurement were performed on each subject with two optodes on the forehead. Main oscillatory frequencies of oxyhemoglobin signal were analyzed. Spectral changes of low frequency oscillations (LFO) between subsequent experimental blocks were used as a marker of cortical response. Cortical response was compared to the level of consciousness of the patients and their functional outcome, through validated clinical scores. Results Cortical hemodynamic response to music on the left prefrontal brain was associated with the level of consciousness of the patients and with their clinical outcome after three months. Conclusions Variations in LFO spectral power measured with fNIRS may be a new marker of cortical responsiveness to detect covert consciousness in neurocritical patients. Left prefrontal cortex may play an important role in the perception of familiar music. Significance We showed the feasibility of a simple fNIRS approach to detect cortical response in the real setting of an intensive care unit

VOLUNTARY CONTROL OF BREATHING ACCORDING TO THE BREATHING PATTERN DURING LISTENING TO MUSIC AND NON-CONTACT MEASUREMENT OF HEART RATE AND RESPIRATION

We investigated if listening to songs changes breathing pattern which changes autonomic responses such as heart rate (HR) and heart rate variability (HRV) or change in breathing pattern is a byproduct of listening to songs or change in breathing pattern as well as listening to songs causes changes in autonomic responses. Seven subjects (4 males and 3 females) participated in a pilot study where they listened to two types of songs and used a custom developed biofeedback program to control their breathing pattern to match the one recorded during listening to the songs. Coherencies between EEG, breathing pattern and RR intervals (RRI) were calculated to study the interaction with neural responses. Trends in HRV varied only during listening to songs, suggesting that autonomic response was affected by listening to songs irrespective of control of breathing. Effective coherence during songs while spontaneously breathing was more than during silence and during control of breathing. These results, although preliminary, suggest that listening to songs as well as change in breathing patterns changes the autonomic response but the effect of listening to songs may surpass the effect of changes in breathing. We explored feasibility of using non-contact measurements of HR and breathing rate (BR) by using recently developed Facemesh and other methods for tracking regions of interests from videos of faces of subjects. Performance was better for BR than HR, and over currently used methods. However, refinement of the approach would be needed to get the precision required for detecting subtle changes