One of the cognitive biases of remembered utility is called the peak–end rule. It affects how people remember the pleasantness or unpleasantness of experiences. It states that a person's overall impression of past events is determined, for the most part, not by the total pleasure and suffering it contained, but by how it felt at its peak and at its end. For example, the memory of a painful colonoscopy is improved if the examination is extended by three minutes in which the scope is still inside but not moved anymore, resulting in a moderately uncomfortable sensation. This extended colonoscopy, despite involving more pain overall, is remembered less negatively due to the reduced pain at the end. This even increases the likelihood for the patient to return for subsequent procedures.
ONe of the cOgNITivE bIases oF remembeReD uTiLity is caLLeD the pEaK–end rule. It AffecTS how PEoplE remEmbeR tHe pLEasantness Or unpleaSAntness oF EXPERiences. it sTAteS thaT a person's overaLl imprEsSIoN of PAsT eveNts iS dEtermiNed, fOr thE most PArT, not by tHE TotAl pleASure anD sUFFeRiNg It coNtaineD, buT bY hOw it FeLt at itS peak and aT its EnD. fOr examPlE, The mEmOrY of A painFUl coLonoscopy is iMPrOved if the examINaTIOn IS exteNdED by three Minutes in WhiCh thE sCOpe IS still iNside but noT MoVEd AnyMore, reSulting in a mODeratEly uNcOmfortable sEnsatiOn. tHIs extendeD COLOnOscopy, desPite invOLviNG MoRe pain OVerall, IS remEMbered less nEGaTivelY dUE to thE reDucEd pAin aT tHe End. thIs eveN increaSES tHe liKElihood For tHE PAtieNT tO return for SUbseQueNT ProcEdurES.