Switching Markov Decoders for Asynchronous Trajectory Reconstruction from ECoG signals in Monkeys for BCI Applications
Publication date: Available online 10 March 2017 Source:Journal of Physiology-Paris Author(s): Marie-Caroline Schaeffer, Tetiana Aksenova Brain-Computer Interfaces (BCIs) are systems which translate brain neural activity into commands for external devices. BCI users generally alternate between No-Control (NC) and Intentional Control (IC) periods. NC/IC discrimination is crucial for clinical BCIs, particularly when they provide neural control over complex effectors such as exoskeletons. Numerous BCI decoders focus on the estimation of continuously-valued limb trajectories from neural signals. The integration of NC suppo...
Source: Journal of Physiology Paris - March 9, 2017 Category: Physiology Source Type: research
Retrospectively supervised click decoder calibration for self-calibrating point-and-click brain-computer interfaces
Publication date: Available online 8 March 2017 Source:Journal of Physiology-Paris Author(s): Beata Jarosiewicz, Anish A. Sarma, Jad Saab, Brian Franco, Sydney S. Cash, Emad N. Eskandar, Leigh R. Hochberg Brain-computer interfaces (BCIs) aim to restore independence to people with severe motor disabilities by allowing control of acursor on a computer screen or other effectors with neural activity. However, physiological and/or recording-related nonstationarities in neural signals can limit long-term decoding stability, and it would be tedious for users to pause use of the BCI whenever neural control degrades to per...
Source: Journal of Physiology Paris - March 7, 2017 Category: Physiology Source Type: research
Recent progress in multi-electrode spike sorting methods
We describe the common properties of these algorithms, as well as their main differences. Finally, we outline the issues that remain to be solved by future spike sorting algorithms. (Source: Journal of Physiology Paris)
Source: Journal of Physiology Paris - March 2, 2017 Category: Physiology Source Type: research
Digital hardware implementation of a stochastic two-dimensional neuron model
This study explores the feasibility of stochastic neuron simulation in digital systems (FPGA), which realizes an implementation of a two-dimensional neuron model. The stochasticity is added by a source of current noise in the silicon neuron using an Ornstein–Uhlenbeck process. This approach uses digital computation to emulate individual neuron behavior using fixed point arithmetic operation. The neuron model's computations are performed in arithmetic pipelines. It was designed in VHDL language and simulated prior to mapping in the FPGA. The experimental results confirmed the validity of the developed stochastic FPGA impl...
Source: Journal of Physiology Paris - February 22, 2017 Category: Physiology Source Type: research
Automated detection of high-frequency oscillations in electrophysiological signals: Methodological advances
Publication date: Available online 21 February 2017 Source:Journal of Physiology-Paris Author(s): Miguel Navarrete, Jan Pyrzowski, Juliana Corlier, Mario Valderrama, Michel Le Van Quyen In recent years, new recording technologies have advanced such that oscillations of neuronal networks can be identified from simultaneous, multisite recordings at high temporal and spatial resolutions. However, because of the deluge of multichannel data generated by these experiments, achieving the full potential of parallel neuronal recordings also depends on the development of new mathematical methods capable of extracting meaningf...
Source: Journal of Physiology Paris - February 21, 2017 Category: Physiology Source Type: research
Automated pulse discrimination of two freely-swimming weakly electric fish and analysis of their electrical behavior during a dominance contest
Publication date: Available online 7 February 2017 Source:Journal of Physiology-Paris Author(s): Rafael T. Guariento, Thiago S. Mosqueiro, Paulo Matias, Vinicius B. Cesarino, Lirio O.B. Almeida, Jan F.W. Slaets, Leonardo P. Maia, Reynaldo D. Pinto Electric fishes modulate their electric organ discharges with a remarkable variability. Some patterns can be easily identified, such as pulse rate changes, offs and chirps, which are often associated with important behavioral contexts, including aggression, hiding and mating. However, these behaviors are only observed when at least two fish are freely interacting. Altho...
Source: Journal of Physiology Paris - February 7, 2017 Category: Physiology Source Type: research
Rhythms dysregulation: A new perspective for understanding PTSD?
Publication date: Available online 1 February 2017 Source:Journal of Physiology-Paris Author(s): Jacques Dayan, Géraldine Rauchs, Bérengère Guillery-Girard Post-traumatic stress disorder (PTSD) is a complex syndrome that may occur after exposure to one or more traumatic events. It associates physiological, emotional, and cognitive changes Brain and hormonal modifications contribute to some impairments in learning, memory, and emotion regulation. Some of these biological dysfunctions may be analyzed in terms of rhythms dysregulation that would be expressed through endocrine rhythmicity, sleep organization, and tempo...
Source: Journal of Physiology Paris - February 1, 2017 Category: Physiology Source Type: research
Intragenus (Campylomormyrus) and intergenus hybrids in mormyrid fish: physiological and histological investigations of the electric organ ontogeny
Publication date: Available online 17 January 2017 Source:Journal of Physiology-Paris Author(s): Frank Kirschbaum, Linh Nguyen, Stephanie Baumgartner, Linda Chi, Rene Wolfart, Khouloud Elarbani, Hari Eppenstein, Yevheniia Korniienko, Lilian Guido-Böhm, Victor Mamonekene, Marianne Vater, Ralph Tiedemann African weakly electric mormyrid fish show a high diversity of their electric organ discharge (EOD) both across and within genera. Thanks to a recently developed technique of artificial reproduction in mormyrid fish, we were able to perform hybridizations between different genera and within one genus (Campylom...
Source: Journal of Physiology Paris - January 17, 2017 Category: Physiology Source Type: research
Karyotype description of the African weakly electric fish Campylomormyrus compressirostris in the context of chromosome evolution in Osteoglossiformes
Publication date: Available online 17 January 2017 Source:Journal of Physiology-Paris Author(s): Julia Canitz, Frank Kirschbaum, Ralph Tiedemann Karyotyping is a basic method to investigate chromosomal evolution and genomic rearrangements. Sixteen genera within the basal teleost order Osteoglossiformes are currently described cytogenetically. Our study adds information to this chromosomal dataset by determining the karyotype of Campylomormyrus compressirostris, a genus of African weakly electric fish that has not been previously examined. Our results indicate a diploid chromosome number of 2n=48 (4sm + 26m + 18a) with...
Source: Journal of Physiology Paris - January 17, 2017 Category: Physiology Source Type: research
Initial uncertainty impacts statistical learning in sound sequence processing
Publication date: Available online 12 January 2017 Source:Journal of Physiology-Paris Author(s): Juanita Todd, Alexander Provost, Lisa Whitson, Daniel Mullens This paper features two studies confirming a lasting impact of first learning on how subsequent experience is weighted in early relevance-filtering processes. In both studies participants were exposed to sequences of sound that contained a regular pattern on two different timescales. Regular patterning in sound is readily detected by the auditory system and used to form “prediction models” that define the most likely properties of sound to be encountered in...
Source: Journal of Physiology Paris - January 12, 2017 Category: Physiology Source Type: research
Advances and limitations of visual conditioning protocols in harnessed bees
Publication date: Available online 18 December 2016 Source:Journal of Physiology-Paris Author(s): Aurore Avarguès-Weber, Theo Mota Bees are excellent invertebrate models for studying visual learning and memory mechanisms, because of their sophisticated visual system and impressive cognitive capacities associated with a relatively simple brain. Visual learning in free-flying bees has been traditionally studied using an operant conditioning paradigm. This well-established protocol, however, can hardly be combined with invasive procedures for studying the neurobiological basis of visual learning. Different efforts have b...
Source: Journal of Physiology Paris - December 17, 2016 Category: Physiology Source Type: research
Neuropeptidomics in Triatoma infestans. Comparative transcriptomic analysis among triatomines
Publication date: Available online 18 December 2016 Source:Journal of Physiology-Paris Author(s): Lucila Traverso, Ivana Sierra, Marcos Sterkel, Flavio Francini, Sheila Ons Chagas’ disease, affecting up to 6-7 million people worldwide, is transmitted to humans through the feces of triatomine kissing bugs. From these, Rhodnius prolixus, Triatoma dimidiata, Triatoma infestans and Triatoma pallidipennis are important vectors distributed throughout the Latin American subcontinent. Resistance to pyrethroids has been developed by some triatomine populations, especially T. infestans, obstructing their control. Given thei...
Source: Journal of Physiology Paris - December 17, 2016 Category: Physiology Source Type: research
Cholinergic influences on vision
Publication date: September 2016 Source:Journal of Physiology-Paris, Volume 110, Issues 1–2 Author(s): Elvire Vaucher (Source: Journal of Physiology Paris)
Source: Journal of Physiology Paris - December 13, 2016 Category: Physiology Source Type: research
Object discrimination through active electrolocation: Shape recognition and the influence of electrical noise
Publication date: Available online 12 December 2016 Source:Journal of Physiology-Paris Author(s): Sarah Schumacher, Theresa Burt de Perera, Gerhard von der Emde The weakly electric fish Gnathonemus petersii can recognise objects using active electrolocation. Here, we tested two aspects of object recognition; first whether shape recognition might be influenced by movement of the fish, and second whether object discrimination is affected by the presence of electrical noise from conspecifics. (i) Unlike other object features, such as size or volume, no parameter within a single electrical image has been found that encode...
Source: Journal of Physiology Paris - December 11, 2016 Category: Physiology Source Type: research
Magnetic orientation in C. elegans relies on the integrity of the villi of the AFD magnetosensory neurons
Publication date: Available online 8 December 2016 Source:Journal of Physiology-Paris Author(s): Chance Bainbridge, Anjelica Rodriguez, Andrew Schuler, Michael Cisneros, Andrés G. Vidal-Gadea The magnetic field of the earth provides many organisms with sufficient information to successfully navigate through their environments. While evidence suggests the widespread use of this sensory modality across many taxa, it remains an understudied sensory modality. We have recently showed that the nematode C. elegans orients to earth- strength magnetic fields using the first pair of described magnetosensory neurons, AFDs. Th...
Source: Journal of Physiology Paris - December 8, 2016 Category: Physiology Source Type: research
