NataTech Citations in Research Archives - Nata Technologies

Efects of Acute Aerobic Exercise on Response Inhibition in Adult Patients with ADHD

super-admin — Sat, 07 Nov 2020 18:53:35 +0000

Experimental task. Te experimental paradigm was programmed using Cogent 2000 v125 (http://www.
vislab.ucl.ac.uk/cogent.php) and Matlab R2015b (Te MathWorks, Inc.) and was projected onto a screen and
presented to the participants in the scanner through a mirror on the head coil. Te distance from the eyes of the
participants to the screen was 50cm. Stimuli were white and displayed on a black background. An MR-compatible
keypad (NAtA Technologies, Coquitlam, Canada) was used to respond with the right hand (see also31,50).
To assess the participants’ ability to inhibit a prepotent response and to sustain attention, a Go/No-go task as
described in Mehren et al.50 was utilized. Letters of the alphabet were presented in an event-related design. Each
trial started with the presentation of a single letter for 0.25sec, followed by a variable post stimulus interval during
which a fxation cross was visible. Trial duration was either 2, 6, or 8sec, with predominantly shorter trials (mean
trial length=3.5 sec). Participants were instructed to respond to every letter (Go trials) by pressing a key with
their right index fnger, except to the letter ‘X’ (No-go trials). Tey were told to focus on the fxation cross during
the entire experiment and to respond as fast and accurate as possible.

http://oops.uni-oldenburg.de/4555/1/2019-102_mehren_article_s41598-019-56332-y.pdf

The post Efects of Acute Aerobic Exercise on Response Inhibition in Adult Patients with ADHD appeared first on Nata Technologies.

Neural substrates underlying motor skill learning in chronic hemiparetic stroke patients

super-admin — Sat, 07 Nov 2020 18:51:44 +0000

Prior to the fMRI activation runs, a resting-state run was acquired except in patients #1–4 and #17. The resting-state acquisition consisted of one single 6-min run during which the patients kept their eyes closed and had to avoid moving or falling asleep.

Then, the patients performed two consecutive activation runs of motor skill learning with their paretic upper limb, using a MR-compatible mouse (NAtA Technologies, Canada). Visual feedback was projected on a screen, which was viewed via a mirror placed on the head coil. As described in a previous study (Lefebvre et al., 2012), each run (duration 8 min 41 s; 172 volumes) contained a REST condition (fixation cross) and three experimental conditions: LEARNING, EASY, and REPLAY. LEARNING required performing the motor skill learning paradigm described below. EASY required moving the cursor back and forth between two horizontal or vertical targets, without speed or accuracy constraint. This condition was designed to explore brain activation related to simple movement execution under visual control. During REPLAY, a video clip of the last LEARNING performance was displayed, and the patients were instructed to follow the cursor’s displacement with their eyes without moving the hand. The REPLAY condition was designed to isolate activation related to visual and oculomotor processes.

https://www.frontiersin.org/articles/10.3389/fnhum.2015.00320/full

The post Neural substrates underlying motor skill learning in chronic hemiparetic stroke patients appeared first on Nata Technologies.

Automatic and fast encoding of representational uncertainty underlies probability distortion

super-admin — Sat, 07 Nov 2020 18:49:56 +0000

Subjects were seated approximately 86 cm in front of a projection screen (Panasonic PT-DS12KE: 49.6 × 37.2 cm, 1024 × 768 pixels, 60-Hz refresh rate) inside the magnetically shielded room. Stimuli were controlled by a Dell computer using Matlab and PsychToolbox-3 (Brainard, 1997; Pelli, 1997). Subjects’ behavioral responses were recorded by an MEG-compatible mouse system (FOM-2B-10B from Nata technologies) and their brain activities by a 306-channel MEG system (see MEG Acquisition and Preprocessing for details).

https://www.biorxiv.org/content/10.1101/2019.12.17.879684v1.full

The post Automatic and fast encoding of representational uncertainty underlies probability distortion appeared first on Nata Technologies.

Intensity-Dependent Effects of Acute Exercise on Executive Function

super-admin — Sat, 07 Nov 2020 18:48:53 +0000

The experimental tasks were projected onto a screen and presented to the participants in the scanner through a mirror on the head coil using Cogent 2000 v125 (http://www.vislab.ucl.ac.uk/cogent.php) and Matlab R2015b (The MathWorks Inc.). The distance from the eyes of the participants to the screen was 50 cm. Stimuli were white and displayed on a black background. Participants used an MR-compatible keypad (NAtA Technologies, Coquitlam, Canada) to respond with their right hand.

https://www.hindawi.com/journals/np/2019/8608317/

The post Intensity-Dependent Effects of Acute Exercise on Executive Function appeared first on Nata Technologies.

Combined expectancies: the role of expectations for the coding of salient bottom-up signals

super-admin — Sat, 07 Nov 2020 18:47:16 +0000

Stimuli were presented on a 22-in. Samsung SyncMaster monitor (spatial resolution 1680 X 1050; refresh rate 120 Hz) at a distance of 60 cm. A chin and forehead rest preserved the distance. The presentation of stimuli and response recording were controlled using PsychoPy psychology software for Python (Peirce 2007, 2008). Participants were provided with button response pads (NAtA Technologies) for each hand and responded by pressing the corresponding button on the button response pad with the left and right index fingers.

https://link.springer.com/article/10.1007/s00221-019-05710-z

The post Combined expectancies: the role of expectations for the coding of salient bottom-up signals appeared first on Nata Technologies.

The Right Temporoparietal Junction Supports Speech Tracking During Selective Listening: Evidence from Concurrent EEG-fMRI

super-admin — Sat, 07 Nov 2020 18:45:48 +0000

fMRI data were acquired on a 3 T Siemens MAGNETOM Verio MRI scanner with a 12-channel head array. Key presses were recorded using an MR-compatible response keypad (Nata Technologies). Acoustic stimuli were delivered via MR-compatible insert earphones (MR confon HP AT01; MR Confon). Participants were equipped with over-ear hearing protectors during the experiment to attenuate scanner background noise. During the selective listening task, 1100 T2*-weighted gradient echo planar imaging volumes with BOLD contrast were obtained (time of repetition [TR] = 2000 ms, time of echo [TE] = 30 ms, flip angle α = 80°, field of view [FoV] = 200 × 200 mm², voxel-size = 3.1 × 3.1 × 3.0 mm³). Volumes consisted of 31 transverse slices with a gap of 0.9 mm in between and were recorded in an ascending order. The same imaging parameters were used to obtain a resting-state time series consisting of 261 T2* volumes. A high-resolution structural volume was acquired for each participant using a T1-weighted magnetization-prepared rapid acquisition gradient echo sequence (TR = 1900 ms, TE = 2.52 ms, α = 9°, FoV = 256 × 256 mm², voxel-size = 1 × 1 × 1 mm³).

https://www.jneurosci.org/content/37/47/11505

The post The Right Temporoparietal Junction Supports Speech Tracking During Selective Listening: Evidence from Concurrent EEG-fMRI appeared first on Nata Technologies.

The Brain Is Faster than the Hand in Split-Second Intentions to Respond to an Impending Hazard: A Simulation of Neuroadaptive Automation to Speed Recovery to Perturbation in Flight Attitude

super-admin — Sat, 07 Nov 2020 18:44:32 +0000

Experimental Tasks

Two different tasks were used, a simple piloting task of level flight over the ocean and a more complex piloting task through the Grand Canyon. We used the first task to develop a method for decoding of neural states associated with response to a perturbation and the second task to investigate the generalizability of the method to a related but more complex situation. In both tasks the participant was given a first-person unobstructed view from the airplane (the view was as if from a camera in the front of the aircraft, see Figures 2A–D). The aircraft model simulated was an F22—Raptor using the X-plane flight simulator (Version 9.75, Laminar Research). The data for various flight parameters (elevator, aileron, rudder deflections, pitch, roll, yaw, heading, speed, dive rate, structural g-forces, latitude, longitude, altitude, etc.) and the control stick (NATA Technologies MRI and MEG compatible) deflections were collected at a mean sampling rate of 400 Hz using a UDP Matlab interface. The experimental conditions could be controlled via Matlab by using the UDP interface to give commands to the flight simulator.

Functional MRI

Our goal to develop a classifier of operator intention to undertake a rapid action to avoid a perturbation was to use a neuroimaging method with high temporal resolution, such as EEG or MEG. We used MEG in the current study, but in order to bolster our ability to localize MEG activity to intracortical sources, we also conducted an fMRI study of the same piloting tasks in order to establish seeds for conducting source localization analyses of MEG data. In the fMRI experiment participants underwent two sessions of the simple piloting task. Visual presentation of the flight simulation was projected by mirrors to a screen behind the head coil that could be viewed by the participant by a mirror mounted on the head coil. An fMRI compatible control stick (NATA technologies) was used by the right hand of the participant to control the elevator (back = pitch up; forward = pitch down) and aileron (roll left and right) deflections. Trigger timing of the fMRI scanning was directly read into one of the flight parameters of the flight simulator by means of a National Instruments Hi Speed USB NI USB-9162 BNC analog to digital converter.

MEG

In the MEG experiment participants underwent three sessions of the simple piloting task and one session of the complex piloting task. The first two sessions of the simple piloting task were used for training the decoding algorithm. The third session of the simple piloting task was used to evaluate the effectiveness of the trained algorithm in decoding neural states when participants perform the same task. As discussed previously, however, an effective classifier should be able to decode not only neural states on the same task that it has been trained on, but on more complex versions of the task that the classifier has not been trained on—that is, whether the classifier can achieve transfer. Accordingly, we also assessed the effectiveness of the classifier in decoding neural activity preceding detection and response to a perturbation in the complex piloting task. Visual presentation of the flight simulation was projected to a mirror to a screen above the participant’s head. An fMRI compatible control stick (NATA technologies) was used by the right hand of the participant to control the elevator (back = pitch up; forward = pitch down) and aileron (roll left and right) deflections. Trigger timing for the start of each trial and the start of the perturbation was registered by a photodiode placed on the screen. A small white square was constantly presented on the lower center part of the screen (out of the view of the participant) at the start of each trial and at the onset of the perturbation the small square turned black for 20 ms. The light intensity change was detected by the photo diode and written directly to one of the extra channels on the MEG.

https://www.frontiersin.org/articles/10.3389/fnhum.2016.00187/full

The post The Brain Is Faster than the Hand in Split-Second Intentions to Respond to an Impending Hazard: A Simulation of Neuroadaptive Automation to Speed Recovery to Perturbation in Flight Attitude appeared first on Nata Technologies.

Activation in human auditory cortex in relation to the loudness and unpleasantness of low-frequency and infrasound stimuli

super-admin — Sat, 07 Nov 2020 18:42:22 +0000

The fMRI measurements were done on a 3-T scanner (Magnetom Prisma 3T, Siemens AG, Erlangen, Germany), equipped with a 20-channel head coil. The response scale and a fixation cross (see below) were projected onto a screen in the scanner bore and could be seen by the participants via a mirror construction mounted onto the head coil. To attenuate acoustic background noise produced by the MRI system, the participants’ left (non-stimulated) ear was occluded with a foam earplug. Additional attenuation was provided by means of fMRI-compatible headphones (OptoACTIVE, Optoacoustics Ltd, Or Jehuda, Israel), which were also used to communicate with the participant in between measurements. Behavioral responses of the participants were collected via an fMRI-compatible response pad (LXPAD-2×5-10M, NAtA technologies, Coquitlam, Canada).

https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0229088

The post Activation in human auditory cortex in relation to the loudness and unpleasantness of low-frequency and infrasound stimuli appeared first on Nata Technologies.

Neural signatures of experimentally induced flow experiences identified in a typical fMRI block design with BOLD imaging

super-admin — Sat, 07 Nov 2020 18:41:14 +0000

The present experimental design resembled that of our previous study (Ulrich et al., 2014). Major changes, however, applied to the length and number of blocks to meet the requirements imposed by the experimental realization as an fMRI block design to measure the blood oxygen level-dependent (BOLD) signal. Subjects performed visually presented mental arithmetic tasks. On each trial, a math expression appeared in black font above an on-screen keyboard in the center of the screen. Stimuli were presented on a white background on MRI compatible video goggles (VisuaStim Digital, Resonance Technology Inc., Northridge, CA, USA) at a resolution of 800 × 600 pixels. The on-screen keyboard was controlled by an MRI compatible trackball (NAtA TECHNOLOGIES, Coquitlam, Canada). Participants were asked to sum the presented two or more numbers in their mind and to enter the result as accurately and as fast as possible using the on-screen keyboard. After a period of 10 s per each math calculation, or when participants had submitted the result, there was a break of 1 s during which the string “xxx + x” appeared on the screen. Calculations and intermitting breaks were presented until the block length of 30 s had elapsed.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4769635/

The post Neural signatures of experimentally induced flow experiences identified in a typical fMRI block design with BOLD imaging appeared first on Nata Technologies.

Unmasking selective path integration deficits in Alzheimer’s disease risk carriers

super-admin — Sat, 07 Nov 2020 18:39:56 +0000

Participants navigated the virtual environments using a joystick (behavioral experiment, Trust GXT 555 Predator; fMRI experiment, MR-compatible joystick from Nata Technologies, Coquitlam, Canada), allowing them to move forward, turn left, or turn right. Moving backward was not possible so that movement direction was equivalent with heading direction. In each subtask, participants’ speed was attenuated when their distance from the center of the arena was larger than 5657 vm and linearly decreased to zero at 6788 vm, ensuring a constant movement radius in subtasks with and without a visible boundary (fig. S1). In this “speed reduction zone,” participants could navigate at full speed when heading toward the center of the arena. The position of the participant was logged every 200 ms, which allowed us to extract movement periods, movement speed, and movement direction.

https://advances.sciencemag.org/content/6/35/eaba1394

The post Unmasking selective path integration deficits in Alzheimer’s disease risk carriers appeared first on Nata Technologies.