Pressing the pad irrespective of the target sequence was counted as miss. However, the volume of distribution is estimated to be higher in oral form than in the intravenous form [ 16 ]. A postmortem study of brain tissue tests and interviews of those close to the deceased ties some psychiatric symptoms to early Alzheimer's disease. Psychiatry and Clinical Neurosciences. After two weeks, the subjects performed the tests again just after 8 hours of their last dose.