an area ofthe brain resembling a folded sheet of grey tissue thatcovers the rest of the brain.The cerebral cortex directs the brains higher cognitive and emotional functions. It is divided into two almostsymmetrical halves called the cerebral hemispheres. Each hemisphere containsfour lobes. Areas within these lobes regulate allforms of conscious experience such as emotion, perception, thought and planning as well as unconscious cognitive and emotional processes. The cerebral cortex includesthe frontal lobe, occipital lobe, parietal lobe and temporal lobe.
this phenomenon arises in some drug categories, such as theopiates (heroin, morphine etc) and tryptamines (LSD,mescaline and psilocybin) when the prolonged use of one drugin the group results in the development of tolerance to theothers opioids.