Effects of suppressing inhibitory synaptic strength on the dynamics of a network of spiking neurons: A computational study*

2. We have carried out a computational study to investigate the effects of a suppression of inhibitory
   
   synaptic weights on the spontaneous activity of networks of spiking neurons. Neuronal networks with
   
   biologically realistic features, which were reconstructed from multi-electrode array recordings taken
   
   in a cortical neuronal culture, and their modifications were used in the numerical simulations. The
   
   magnitudes of the synaptic weights of all the inhibitory connections were decreased by a uniform amount
   
   subjecting to the condition that inhibitory connections would not be turned into excitatory ones. We have
   
   found that the responses of individual neurons within a network to such a suppression of inhibition is
   
   heterogeneous: the firing rate of some neurons increases as expected but the firing fate of the other neurons
   
   decreases or remains unchanged. The fraction of neurons having an increase in their firing rate increases as
   
   the magnitude of the reduction in the inhibitory synaptic weights is increased. A variability in the overall response
   
   of the whole network was also found. Upon the suppression of inhibition, the average firing rate of the whole
   
   network increases for networks that have bursting but remains unchanged for networks without bursting.