Each person can be affected differently by a concussion, he says, and each concussion can harm different parts of the brain or produce different symptoms.

Patients are affected differently, depending on the illness, the severity of that illness, interventions and medications, such as chemotherapy.

Different populations may be affected differently by accidents.

Individual susceptibility can vary from day to day, and different individuals under the same conditions may be affected differently or not at all.

Each region will be affected differently based on the different climate and temperature fluctuations.