Naturalistic Environments Neuroscience 2024 NIRS Publication
Naturalistic Environments
With the advent of portable and wearable solutions, in addition to its intrinsic performance in the presence of movements, fNIRS is currently the ideal solution for studies that intend to evaluate cortical actitiy within naturalistic environments.
Cognitive States
fNIRS adds another dimension to studies investigating cognitive functions and mental states, since it is a portable technique not too sensitive to motion artifacts. Attention processes, inhibition mechanisms, and working memory, as well as other cognitive states, may be studied in natural environments with a fast setup preparation.
Motor Execution
Motor execution and fine movements depend on coordinated action of brain function and peripheral muscles. Its portability, ease of use in natural environments, and compatibility with bioelectric measures make fNIRS an optimal choice for studies investigating motor execution.
Emotions
Near-infrared spectroscopy is non-invasive and particularly well suited for evaluating activity in the prefrontal cortex, one of the regions involved in emotional processing. More specific areas related to emotional processing, such as the frontopolar cortex, are easily accessible for measurements by NIRS, making the technique particularly suited to explore the emotional domain.
Social Interaction
The ability of fNIRS to measure two or more subjects simultaneously, enables researchers to study cortical activity in response to social interaction. This way, a new dimension is added to studies investigating topics such as empathy, competitive and cooperative tasks, mother-child interactions and truth telling.
Speech and Language
Realistic experiments involve verbalized speech. As such, they should account for the muscle movements that are required for this process, and the eventual artifacts that these may cause. The robustness of fNIRS in the presence of muscle movements as well as its portability in comparison to other imaging techniques, render this technology a very promising tool for studying speech and language under a great variety of conditions.
Connectivity
fNIRS brings connectivity studies to a new level. The hyperscanning modality enables both online feedback as well as offline analysis regarding within- and between-subjects connectivity. In addition to that, fNIRS fast sampling rate for hemodynamic states allows for a quick update rate of connectivity feedback, resulting into enhanced subject engagement.
Developmental Changes
The portability of fNIRS, its performance in presence of general movements and the feasibility it offers in exploring cortical responses in social environments, represent the greatest advantages for studies on brain functional changes during development of infants and children.
Infant
Infant monitoring is based on continuous measurements of cortical activity within a population that may be characterized by its constant movement. The low sensitivity of fNIRS to motion artifacts make this technique an ideal choice for studies intended to explore the many unknown features of the infant brain.
Neuroeconomics
A key interest of neuroeconomics research is value-based decision making, in which the prefrontal lobe is an important player. Although prefrontal activity has been explored with fMRI, the restricted environment does impose a limit to the number of applications that can be explored. fNIRS may represent a conspicuous improvement to the field, as it enables outdoor measurements that can be combined with simultaneous Eye-Tracking.
Somatosensory
fNIRS determines changes in hemoglobin oxygenation in the human head non-invasively, and has the advantage of being more robust to motion artifacts than fMRI. In addition, the application of fNIRS is more convenient for somatosensory research, especially when measuring patients with chronic pain, as measurements can take place on a more comfortable bench compared to the MR scanner bench.
Multi-modal
In order to render measurements more robust, information may be provided by different modalities. Many groups appreciate multi-modal applications with fNIRS. Typical combinations are fNIRS and EEG, Eye-Tracking or fMRI, but tDCS and TMS have also been applied to concurrently modulate brain activity.
Visual Stimulation Auditory System
As fNIRS measurements are characterized by silent operations, innumerous possibilities of studies intended to explore cortical activation in the presence of controlled sounds can be achieved. Besides a better understanding of auditory processes in the brain, this may facilitate critical improvements on current solutions for cochlear implants.
Brain-Computer Interface (BCI)
Given its great performance in the presence of muscle movements and the possibility of setting up measurements in realistic environments, fNIRS presents itself as an ideal candidate for the acquisition of cortical signals as reliable and representative inputs for Brain-Computer Interface investigations.
Event-Related Optical Signal
fNIRS is potentially the only imaging method that may be capable to measure both hemodynamics and neuronal activity. The Event-Related Optical Signal, caused by changes in light scattering from activated neurons, is observable when employing high frequency sampling with fNIRS.
NIRS fNIRS
The NIRSport2 system is our most technologically advanced fNIRS platform with a range of features and functions unparalleled within the market. With the highest-class of components as our starting point we’ve engineered a system boasting impressive signal quality, extensive versatility, modularity, along with the foresight into future research needs to ensure the most optimal user experience and highest success in science possible
NIRS fNIRS Amplifier NIRSport2
Sampling rate: NIRSport2 comes with a maximal data sampling rate of up to 240 Hz.
NIRS fNIRS Source-detector separation
Source-detector separation: NIRSport2 allows multi-distance measurements between 8mm-5cm.
NIRS fNIRS short-channels solution
Dedicated short-channels solution: NIRSport2 implements 8 mm short channels with the possibility of providing one short channel per source.
NIRS fNIRS Amplifier NIRSport2 recording via Wi-Fi or USB cable
System Connectivity: The NIRSport2 can be connected to the recording laptop both via Wi-Fi or USB cable. The system broadcasts a Wi-Fi connection whose radius can be enhanced up to 10m using a TP-Link.
NIRS fNIRS Amplifier NIRSport2 source illumination with parallel detection
Optimized illumination pattern: the NIRSport2 can run from full-time-multiplexing (individual source illumination with parallel detection) to 4-source frequency encoding (source illumination with parallel detection)
NIRS fNIRS Amplifier NIRSport2 Real-time individual channel coupling quality feedback
Real-time individual channel coupling quality feedback during the source brightness optimization
NIRS fNIRS Amplifier NIRSport2 high-powered LED sources
Source output brightness: The NIRSport2 operates with high-powered LED sources (1.0v, max 33 mW per wavelength)
NIRS fNIRS Amplifier NIRSport2 recording laptop or onboard memory
Data recording: The NIRSport2 can store data both on the recording laptop or onboard memory, allowing standalone measurements outside the laboratory environment
NIRS fNIRS NIRSport2 can be placed in a backpack or on a hip belt
Portability: the system can be placed in a backpack or on a hip belt - part of the system starter kit - which ensures weight redistribution in participants with impaired movement
NIRS fNIRS BCI NIRSport2 system allows multimodal recordings LSL
Built-in synchronization and real-time analysis capabilities: the NIRSport2 system allows multimodal recordings by supporting wired (TTL) and wireless (Lab Streaming Layer) synchronization protocols, tested for an error within a few milliseconds
NIRS fNIRS ICBM-152 head model 37 cm to about 60cm
Dedicated (free) optode configuration software: NIRx NIRSite is a visual GUI-based tool that specifies the arrangement of NIRS sources and detectors on the widely-used ICBM-152 head model. EEG landmarks are provided as guidance. Both adults and infant atlases are available to help to place the optodes in the correct position using the 10/10 or 10/20 system positions for a head circumference from about 37 cm to about 60cm
NIRS fNIRS Hyperscanning Neuroscience Research
Hyperscanning capability: three NIRSport2 can be simultaneously linked to one recording laptop. The set up and recordings can be administered through one interface, the hyperscan app
NIRS fNIRS Amplifier three NIRSport2 8x8 can be combined to achieve up to 94 channels
Number of channels: three NIRSport2 8x8 can be daisy chained to achieve a 24x24 coverage. The recording software sees the three devices as one single divide, allowing for cross-channels and major coverage. A NIRSport 24x24 can be combined to achieve up to 94 channels (70 standard channels ~3cm spacing, 24 short detector channels ~8mm)
NIRS fNIRS with Physiological measurement
Physiological measurement: The NIRSport2 can be combined with the NIRxWINGS module for synchronous recording of physiological measurements such as ECG, HR, respiration, muscular activity, PPG, SpO2, and GSR to improve data quality
NIRS fNIRS Amplifier NIRSport2 Software and warranty
Software License Key: NIRx offers unlimited licenses for a lifetime for its data acquisition (Aurora), montage design (NIRSite), and basic data analysis software (NirsLab).
System warranty: NIRx offers a standard 3-year warranty, which can be extended up to 5 years, and can provide spare parts for up to 7 years
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