Qualcomm Corporate R&D, San Diego, CA 92121, USA.
IEEE Trans Neural Syst Rehabil Eng. 2011 Jun;19(3):317-24. doi: 10.1109/TNSRE.2011.2117441. Epub 2011 Mar 3.
Cortical microstimulation has been proposed as a method to deliver sensory percepts to circumvent damaged sensory receptors or pathways. However, much of perception involves the active movement of sensory organs and the integration of information across sensory and motor modalities. The efficacy of cortical microstimulation in such an active sensing paradigm has not been demonstrated. We report a novel behavioral paradigm which delivers microstimulation in real-time based on a rat's movements and show that rats can perform sensorimotor integration with electrically delivered stimuli. Using a real-time whisker tracking system, we delivered microstimulation in barrel cortex of actively whisking rats when their whisker crossed a particular spatial location which defined the target. Rats learned to integrate microstimulation cues with their knowledge of whisker position to infer target location along the rostro-caudal axis in less than 200 ms. In a separate experiment, we found that rats trained to respond to cortical microstimulation responded similarly to whisker deflections while ignoring auditory distracters, suggesting that barrel cortex stimulation may be perceptually similar to somatosensory stimuli. This ability to deliver sensory percepts using cortical microstimulation in an active sensing system might have significant implications for the development of sensorimotor neuroprostheses.
皮层微刺激已被提议作为一种提供感觉知觉的方法，以绕过受损的感觉受体或途径。然而，许多感知涉及感觉器官的主动运动和感觉和运动模态之间的信息整合。皮层微刺激在这种主动感知范式中的功效尚未得到证明。我们报告了一种新的行为范式，该范式根据大鼠的运动实时提供微刺激，并表明大鼠可以用电刺激进行感觉运动整合。使用实时胡须跟踪系统，当大鼠的胡须穿过特定的空间位置定义目标时，我们在活跃的胡须皮层中提供微刺激。大鼠在不到 200 毫秒的时间内学会将微刺激线索与其对胡须位置的了解相结合，以推断沿头尾轴的目标位置。在另一个实验中，我们发现，经过训练对皮层微刺激做出反应的大鼠对胡须的偏转反应相似，而忽略了听觉干扰，这表明桶状皮层刺激可能在感知上类似于躯体感觉刺激。这种在主动传感系统中使用皮层微刺激提供感觉知觉的能力可能对感觉运动神经假体的发展具有重要意义。
