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1/9. brain-computer communication: self-regulation of slow cortical potentials for verbal communication.

    OBJECTIVE: To test a training procedure designed to enable severely paralyzed patients to communicate by means of self-regulation of slow cortical potentials. DESIGN: Application of the Thought Translation Device to evaluate the procedure in patients with late-stage amyotrophic lateral sclerosis (ALS). SETTING: Training sessions in the patients' homes. PARTICIPANTS: Two male patients with late-stage ALS. INTERVENTIONS: patients learned voluntary control of their slow cortical potentials by means of an interface between the brain and a computer. Training was based on visual feedback of slow cortical potentials shifts and operant learning principles. The learning process was divided into small steps of increasing difficulty. MAIN OUTCOME MEASURES: Accuracy of self-control of slow cortical potentials (percentage of correct responses). learning progress calculated as a function of training session. RESULTS: Within 3 to 8 weeks, both patients learned to self-regulate their slow cortical potentials and to use this skill to select letters or words in the language Support Program. CONCLUSIONS: This training schedule is the first to enable severely paralyzed patients to communicate without any voluntary muscle control by using self-regulation of an electroencephalogram potential only. The protocol could be a model for training patients in other brain-computer interface techniques.
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keywords = communication
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2/9. A non-invasive communication device for the paralyzed.

    An EEG-based communication system has been developed to re-establish communication in severely paralyzed patients who operate the device by generating shifts of their slow cortical potentials. Training to gain control over slow cortical potentials was based on visual feedback and operant conditioning strategies. The vertical movement of a graphic signal on a computer screen informs the patients about the course of their slow cortical potential amplitude. Positive slow cortical potential shifts move the cursor up, negative shifts move it down. These shifts are then translated into binary responses. When a patient has achieved reliable control over his/her slow cortical potential shifts, these responses can be used to select or reject items presented at the bottom of the screen. As learning processes and applications differ considerably between patients, the present paper describes the data from one patient with amyotrophic lateral sclerosis. After about three months of training, this patient gained stable, near-perfect control over his slow cortical potentials. This skill enabled him to operate a specially designed program to communicate messages to his caregivers.
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ranking = 0.75
keywords = communication
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3/9. Conscious perception of brain states: mental strategies for brain-computer communication.

    Direct brain-computer communication utilises self-regulation of brain potentials to select letters, words or symbols from a computer menu. In this study a completely paralysed (locked-in) patient learnt to produce slow cortical potential (SCP) shifts to operate a binary spelling device. After hundreds of training sessions he gave a detailed description of his mental strategies for self-regulation. His cognitive strategies matched with the electrocortical changes perfectly. Thus he produced a contingent negative variation (CNV) with images of preparation such as an arrow being drawn on a bow. To produce a positive potential shift he imagined the arrow shooting up from the bow. To suppress potential shifts he tried to stop thinking. The study demonstrates that patients become sensitive for their brain states with increasing self-regulation practice. The use of conscious cognitive strategies may, however, be incompatible with the complete automatization of the self-regulation skill.
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ranking = 0.625
keywords = communication
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4/9. Automatic processing of self-regulation of slow cortical potentials: evidence from brain-computer communication in paralysed patients.

    OBJECTIVE: Direct brain-computer communication utilizes self-regulation of brain potentials to select letters, words or symbols from a computer menu. Selection of letters or words with brain potentials requires simultaneous processing of several tasks such as production of certain brain potentials at predefined time points simultaneously with processing of presented letter strings. This study addresses the question of whether the self-regulation of slow cortical potentials (SCP) automatizes with practice and can thus be considered as a skill comparable to motor or cognitive skills. methods: Two nearly completely paralysed patients learned over several months to produce electrocortically negative and positive SCP by means of visual feedback. Improved performance and a reduction in performance variability were regarded as behavioural indicators for automaticity, while the topographic focalization of cortical activation was considered as a neurophysiological indicator for automaticity. Different indicators of automaticity were expected to covary along with practice. RESULTS: In patient 1, performance measured as the percentage of correct SCP shifts increased simultaneously with the topographic focalization of cortical activation. His performance became more stable with practice. For this patient the criteria for automaticity were all met. In patient 2, performance also improved, but his cortical activity became topographically less focal. His performance was less stable than that of patient 1. CONCLUSIONS: The present findings, albeit on only two subjects, provide preliminary evidence that SCP self-regulation may automatize with long-term practice and can therefore be considered a skill.
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ranking = 0.625
keywords = communication
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5/9. ALS--decision making under uncertainty: a positive approach.

    amyotrophic lateral sclerosis (ALS) is a progressive motor neuron disease. It is characterized by feelings of uncertainty and predictable crises points where difficult decisions have to be made by both the client and the family. These crises points involve progressive and sometimes sudden impairment in mobility, communication, nutrition and ultimately, respiratory function. This paper will use case analysis to illustrate the decisions that have to be made at each crisis point. A model will be presented that will focus on the nursing assessment of decision making behaviours of families experiencing the crisis of a debilitating illness. Emphasis will be on educating the client and family to anticipate what to expect and what decision making strategies they can use. In addition, recent literature will be presented that reviews nursing interventions designed to improve the quality of life of the client and family during these difficult time periods.
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ranking = 0.125
keywords = communication
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6/9. Speech deterioration in amyotrophic lateral sclerosis: a case study.

    Few detailed reports have been published on the nature of speech and voice changes during the course of amyotrophic lateral sclerosis (ALS). The subject of this case study is a woman who was diagnosed as having ALS with bulbar signs at the age of 53. speech intelligibility, pulmonary function, and selected speech and voice functions were tested during an approximately 2-year course of her disease. Over this period, her speech intelligibility, as measured by a multiple-choice word identification test, declined from 98% to 48%. Phonetic features that were most affected during the intelligibility decline included voicing contrast for syllable-initial and syllable-final consonants, place of articulation contrasts for lingual consonants, manner of articulation for lingual consonants, stop versus nasal manner of production, features related to the liquid consonants, and various features related to syllable shape. An acoustic measure, average slope of the second-formant frequency, declined in association with the intelligibility reduction and is thought to reflect the loss of lingual motoneurons. Her pulmonary function also declined over the observation interval, with particularly severe reduction in measures of air flow. Oral diadochokinesis and measures of vocal function (including jitter, shimmer, and signal-to-noise ratio) were highly variable across test sessions. These results are discussed in terms of the challenges they present to sensitive assessment of change and to management of the communication disability in ALS.
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ranking = 0.125
keywords = communication
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7/9. Bulbar amyotrophic lateral sclerosis: patterns of progression and clinical management.

    patients with bulbar amyotrophic lateral sclerosis (ALS) are often referred to the otolaryngologist/head and neck surgeon and speech pathologist for evaluation and management of dysphagia and dysarthria. These patients comprise an unusual group because of the progressive and multi-system nature of their illness. The neuromuscular disabilities associated with bulbar ALS cause a myriad of related symptoms associated with swallowing, speech, and respiration. Although the rate of progression cannot be predicted, a general pattern of progression is noted. Bulbar disease accounts for the majority of the worst symptoms of ALS. The loss of the ability to swallow changes eating from a pleasurable task to a burden of survival. Loss of communication effectively imprisons the patient in a state of isolation. The progressive weakness of respiration, predominantly a spinal rather than bulbar manifestation, is the cause of death for nearly all ALS patients and is also discussed. The general patterns of progression of bulbar ALS are outlined in this paper. The development of symptoms are correlated with specific treatment recommendations to aid the clinician in devising an orderly plan of management for this progressive disease.
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ranking = 0.125
keywords = communication
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8/9. Treatment efficacy: dysarthria.

    The dysarthrias form a group of diverse, chronic motor speech disorders. The disorders of Parkinson's disease, stroke, traumatic brain injury, amyotrophic lateral sclerosis, and cerebral palsy are reviewed because they represent important clinical diagnoses in which dysarthria is a frequent and debilitating symptom. The roles played by speech-language pathologists include participation in differential diagnosis, provision of speech treatment, staging of treatment, and timely education so that clients and families can make informed decisions about communication alternatives. Both scientific and clinical evidence is presented that suggests that individuals with dysarthria benefit from the services of speech-language pathologists. Group-treatment studies, single-subject studies, and case reports illustrate the effectiveness of various types of speech treatment. research into the effectiveness of augmentative and alternative communication systems for individuals with cerebral palsy is also presented.
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ranking = 0.25
keywords = communication
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9/9. Restoration of neural output from a paralyzed patient by a direct brain connection.

    patients with severe paralysis of limbs, face and vocal apparatus may be intelligent and aware and yet, tragically, unable to communicate. We describe a communication link for such a 'locked-in' patient with amyotrophic lateral sclerosis. We recorded action potentials in her brain over several months by means of an electrode that induces growth of myelinated fibers into its recording tip. She was able to control the neural signals in an on/off fashion. This result is an important step towards providing such patients with direct control of their environment by interfacing with a computer. Additionally, it indicates that restoration of paralyzed muscles may be possible by using the signals to control muscle stimulators.
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ranking = 0.125
keywords = communication
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