BitFlow Axion-CL frame grabber helps scientists track high-speed micromotions of rodent whiskers
Rodents use their whiskers to explore their environment and discover objects in their immediate vicinity. While whiskers themselves do not have nerves, the active back and forth rhythmic movement of whiskers over surfaces produces a neural representation of complex tactile scenes. This neural process allows rodents to navigate in their native environment of tunnels and dark burrows, find and identify items, and guide their movement along walls.
Recently, researchers at the University of Illinois Urbana-Champaign investigated how high-frequency energy bursts produced by whisker movements are transformed into distinct “bar codes” carrying a significant amount of information. Their findings may shed light on the neural coding in other whisker-like sensory organs across the animal world as well as in texture perception of primate skin.
Video Synchronized with Acoustics
The researchers from the University of Illinois employed high-speed videography in tandem with sensitive acoustical measurements to carry out their studies in detail. They discovered a systematic sequence of vibrational modes with frequencies up to 10kHz by observing the whiskers’ micromotions. From there, they formulated a hypothesis that a rodent’s whiskers are essentially pre-neural processors that transform the micromotions into temporal code with ultra-high Kb/s bandwidth. Temporal coding, in this instance, refers to a neural code that uses the precise timing or high-frequency fluctuations of neural firing rates to carry information.
For the video portion of the tests, whisker movements across various objects were simultaneously recorded in two orthogonal planes. Video in the xy plane was captured using a Mikrotron EoSens 3.0MCL three-megapixel camera, mounted overhead, configured at a resolution of 656 × 600 pixels and a rate of 1000 to 1500 frames per second (fps). The Mikrotron camera was equipped with a 0.36× telecentric lens that produced a 25 mm × 23 mm field-of-view (FOV). Video in the yz plane was captured using a side camera set at 659 × 494 pixels at 120 fps and a 16 mm lens that produced 34 mm × 23 mm FOV.
Video streams from both cameras were simultaneously transmitted by a BitFlow Axion-CL Camera Link two-channel frame grabber to a PC controlled by NorPix StreamPix multicamera software. Each frame was triggered by the Axion-CL frame grabber, and time stamps were generated with less than 1ms jitter. The BitFlow frame grabber benefits from a PCIe Gen 2 interface and a DMA optimized for fully loaded computers. The video system was illuminated by an overhead LED light focused with 40mm focal length aspheric condenser.
During the experiment, rodent whiskers were swept over an object such as a pole, grating or sandpaper, to mimic interaction in the natural environment. Within each sweeping period, the video frame that captures the whisker “first touch” event was manually identified and then time-aligned to the onset of a large voltage peak in the microphone signal recording. Whiskers outside the camera field of view were subtracted from each original frame, resulting in a high contrast processed frame.
Collisions of moving whiskers against objects create time-varying forces at the whisker follicle, producing a barrage of neural discharges leading to “haptic perception,” that is, the sensory process of gaining information about objects through touch. The scientists discovered that a single micro-collision of a whisker with the surface generates vibrational spanning frequencies up to 10 kHz. While propagating along the whisker, these high-frequency modes can carry up to 80% of shockwave energy, exhibit 100× smaller damping ratio, and arrive at the follicle 10× faster than low frequency components.
Ding, Y., Vlasov, Y. Pre-neuronal processing of haptic sensory cues via dispersive high-frequency vibrational modes. Sci Rep 13, 14370 (2023)
About BitFlow
BitFlow has been developing reliable, high-performance Frame Grabbers for use in imaging applications since 1993. BitFlow is the leader in CoaXPress and Camera Link frame grabbers, building the fastest frame grabbers in the world, with the highest camera/frame grabber densities, triggering performance, and price. With thousands of boards installed throughout the world, into hundreds of imaging applications, BitFlow is dedicated to using this knowledge and experience to provide customers with the best possible image acquisition and application development solutions. BitFlow, located in Woburn, MA, has distributors and resellers located all over the world including Asia, the Americas, and Europe. BitFlow was acquired by Advantech in 2023.
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Advantech’s corporate vision is to enable an intelligent planet. The company is a global leader in the fields of IoT intelligent systems and embedded platforms. To embrace the trends of IoT, big data, and artificial intelligence, Advantech promotes IoT hardware and software solutions with the Edge Intelligence WISE-PaaS core to assist business partners and clients in connecting their industrial chains. Advantech is also working with business partners to co-create business ecosystems that accelerate the goal of industrial intelligence.
