alzeimer's

Dementia is really a clinical syndrome seen as a impairment of multiple higher cortical functions including memory, orientation, thinking, comprehension, calculation, capacity for learning, language, judgment, executive function and visuo-spatial function. It‘s usually accompanied or preceded by deterioration in emotional control, social behavior or motivation. 

Alzheimer's disease is the most typical reason for dementia. Sporadic cases usually present after 60 year while familial types are rare and present in 60 year of age (early-onset dementia ). 

Short-term memory loss is the most typical early symptom. Other spheres of cognitive impairment manifest after several years.