Temporal lobe
Different types of head trauma could also lead to dysfunctions that relate to what the afflicted brain area controls. In humans, the olfactory bulb is located on the inferior side of the brain. Physical damage to this area would alter how the area processes information in a variety of ways, but there are also diseases that can alter how this area works. If the part of the brain that interprets these input signals is damaged, then a distorted output is possible. This would also lead to parosmia. Temporal lobe epilepsy has led to cases of parosmia, but these were only temporary; the onset of parosmia was a seizure and it typically lasted a week or two after. Parosmia is sometimes associated with Parkinson's disease. Although the specific pathway is undetermined, the lack of dopamine has resulted in documented cases of parosmia and phantosmia.