Wellcome Centre for Integrative Neuroimaging (WIN), Department of Experimental Psychology, University of Oxford, Oxford, United Kingdom.
Department of Psychiatry, University of Oxford, Warneford Hospital, Oxford, United Kingdom.
Elife. 2021 May 11;10:e60988. doi: 10.7554/eLife.60988.
Choices rely on a transformation of sensory inputs into motor responses. Using invasive single neuron recordings, the evolution of a choice process has been tracked by projecting population neural responses into state spaces. Here, we develop an approach that allows us to recover similar trajectories on a millisecond timescale in non-invasive human recordings. We selectively suppress activity related to three task-axes, relevant and irrelevant sensory inputs and response direction, in magnetoencephalography data acquired during context-dependent choices. Recordings from premotor cortex show a progression from processing sensory input to processing the response. In contrast to previous macaque recordings, information related to choice-irrelevant features is represented more weakly than choice-relevant sensory information. To test whether this mechanistic difference between species is caused by extensive over-training common in non-human primate studies, we trained humans on >20,000 trials of the task. Choice-irrelevant features were still weaker than relevant features in premotor cortex after over-training.
选择依赖于将感觉输入转化为运动反应。使用侵入性的单个神经元记录，通过将群体神经反应投射到状态空间中，可以跟踪选择过程的演变。在这里，我们开发了一种方法，允许我们在非侵入性的人类记录中以毫秒级的时间尺度恢复类似的轨迹。我们在与上下文相关的选择过程中采集的脑磁图数据中，选择性地抑制与三个任务轴、相关和不相关的感觉输入以及反应方向相关的活动。来自运动前皮层的记录显示出从处理感觉输入到处理反应的进展。与之前的猕猴记录不同，与选择不相关的特征相关的信息比选择相关的感觉信息的表示要弱。为了测试这种物种间的机制差异是否是由于非人类灵长类研究中常见的过度训练引起的，我们在该任务上对人类进行了超过 20000 次的训练。在过度训练后，运动前皮层中与选择不相关的特征仍然比相关特征弱。
