Fig. 1: Mice gained volitional control of the BCI within 10 days.
a Schematic of BCI set-up in awake mice. Six neurons were selected to drive a one-dimensional auditory cursor. In all cases, three direct positive (DP, purple), and three direct negative (DN, brown) neurons were selected. b The control signal was mapped to 6 auditory feedback pitch frequencies; the target pitch frequency was 15 kHz. Example trial in a trained mouse. The calcium signal of individual direct neurons was acquired at 15.5 Hz and accumulated for three frames prior to updating the pitch frequency. Pre-trial start epoch (1 s minimum, gray shading) ended when no running was detected and the control signal was less than the target threshold. The time of success was defined as the time at which the target threshold was reached, 2.6 s in this case. c Example activity of 6 direct neurons (200 s for each condition). The same direct neurons were selected across sessions (insets). The total number of success (green) and failure (gray) trials in the session is indicated below. d Fraction of trials in which the target was reached. The first BCI session ID in which the linear regression was significant is referred to as the ‘learning point’ (arrow; mouse #1, p = 0.013, n = 10 sessions; mouse #2, p = 0.023, n = 6 sessions; mouse #3, p = 0.005, n = 8 sessions; mouse #4, p = 0.005, n = 10 sessions). Sessions in which performance was significantly higher than session 1 are indicated in black (2-sample proportions Z-test, corrected for 12,13,16 or 11 multiple comparisons for mouse #1–4 respectively). e Null distributions used to calculate chance performance, for each mouse (n = 1000). The target threshold and session numbers for each distribution was matched to the threshold used in the corresponding experimental conditions. In all four mice, the actual R2 value (red solid line) was greater than the 95th percentile (one-sided) of the null distribution (dashed line). Source data are provided as a Source Data file.
