After humans die, some cells increase their activity and grow to huge proportions. Fresh human brain samples were collected from postmortem brains to understand human neuropsychiatric disorders. While comparing postmortem brain samples to fresh human neocortex samples, the fresh human brain transcriptome had an entirely unique transcriptional pattern. To understand this difference, scientists measured genome-wide transcription as a function of time from the moment of the fresh tissue removal to mimic the postmortem tissue. Within a few hours, there was an increase in astroglial and microglial gene expression. The gene expression of the two types of cells occurred for twenty-four hours after tissue resection. The understanding of this phenomenon is important to scientists that study human brain disorders. The scientists must account for this when studying human brain disorders.