Before revision:  We identify the tuning parameters , which are consistent with experiments , and show that scale-free neural avalanches occur only at the critical point .
After revision:  The neural avalanches are defined using causal connections between the firing neurons. We analyze the scaling of causal neural avalanches as the critical point is approached from the absorbing phase. By using cluster analysis tools from percolation theory, we characterize the critical properties of the neural avalanches. We identify the tuning parameters , which are consistent with experiments , and show that scale-free neural avalanches occur only at the critical point .