10-06-2017, 06:55 AM
The Thought-Translation Device (TTD)
The TTD consists of a training
device and spelling program for the completely paralyzed using slow-cor-
tical brain potentials (SCP)., the self-regulation
of SCPs is learned through visual-auditory feedback and positive reinforce-ment of SCPs duirng the learning phase. during the spelling phase, patients select letters or words
wiht their respective SCP's. BOLD-response was recorded in functional magnetic resonance
imaging(MRI) as part of investigating the neurophysiological and anatomical basis of SCP. The studies conducted showed the involvement of basal ganglia and premotor cortex
for required SCP positivity.
Technology and functioning:
In the present embodiment, , the core of the TTD consists of a single computer
program written in Visual cpp that runs under all Microsoft Windows versions and it includes the functions of electroencephalogram (EEG)-acquisition,
storage, signal processing, classification, and various applications
for brain computer-communication such as spelling. The patient receives
visual feedback on a separate monitor and/or auditory feedback. The
TTD-software can be connected to several EEG amplifier systems. an eight-channel EEG-amplifier with a time constant of 16 s is connected to an A/D-converter
in the patient's home which serves as the interface to
the TTD.
The proposed TTD also encompasses a psychophysiological system for detection of cognitive functioning in locked-in-syndrome, vegetative
state, apallic syndrome, and coma. The TTD and BCI-2000 permit recording and online-feedback and
reinforcement of slow cortical potentials (SCPs), ERPs, mu rhythm,
and other EEG signals in frequency bands up to 40 Hz. For patients unable to select letters and with no remaining visual func-
tion a digital yes noversion allows the patient to respond to ex-
ternal questions with a brain response, e.g., a negative or positive SCP
polarization in a continuous fashion.
NEUROBEHAVIORAL MECHANISMS OF
PHYSIOLOGICAL CONTROL OF SCPS
More recent investigations used fMRI and
transcranial magnetic stimulation (TMS) in healthy subjects and in
patients at various stages of the learned acquisition of SCP self-contro
l. fMRI-recorded BOLD responses averaged
over five trained subjects able to produce large cortical positives and negatives. Each trial included 70 trials for positivity and 70 for negativity. Awareness of these cognitive-attentional strategies is not
necessary for successful operant brain regulation.
For more details , visit:
http://accenetdownloads/reference/ACCE_S..._Malik.pdf