Alzheimer’s disease is the most common type of dementia. Dementia is characterized by a group of symptoms that severely affect an individual’s mental abilities, interfering significantly with daily functioning.

Early Symptoms of Alzheimer’s Disease

Alzheimer’s is a progressive, degenerative disease that begins with mild memory loss and eventually leads to complete mental impairment. Early Alzheimer’s symptoms may include:

  • Difficulty communicating with others
  • Difficulty performing familiar tasks
  • Disorientation
  • Memory loss
  • Mood and behavioral changes
  • Poor or reduced judgment.

These early Alzheimer’s symptoms usually begin to appear around 60 to 65 years of age.

As the disease progresses, the symptoms of Alzheimer’s become more apparent and more severe. Mid and late-stage symptoms of Alzheimer’s can be divided into two basic categories: cognitive and psychiatric symptoms.

Cognitive Symptoms of Alzheimer’s Disease

Cognitive abilities refer to the mental processes required to carry out mental and physical tasks. The four main cognitive symptoms of Alzheimer’s are referred to as the “four A’s of Alzheimer’s.” These include:

  • Agnosia: Agnosia refers to an individual’s lack of ability to perceive and properly interpret information gleaned with their five senses. An individual with Alzheimer’s disease will not be able to recognize once familiar people, places, smells and sensations (such as pain).
  • Amnesia: Amnesia is the loss of memory. Alzheimer’s sufferers lose their ability to remember people, facts, places and events. Short-term memory, or recently acquired information, is affected first, followed by long-term memory.
  • Aphasia: Aphasia is the inability to both understand and communicate. Individuals with Alzheimer’s disease may have difficulty speaking, writing, reading or listening effectively. They may have difficultly with all or some of these methods of communication.
  • Apraxia: Apraxia refers to the inability to perform physical tasks. This is a gradual decline. Initially, the individual will lose the ability to carry out complicated tasks (such as job-related skills). Next, basic tasks such as eating and getting dressed will be forgotten. Finally, the individual may lose their ability to perform naturally instinctive actions, such as swallowing.

Psychiatric Symptoms of Alzheimer’s

Alzheimer’s is also accompanied by a variety of psychiatric symptoms. Alzheimer’s disease can alter mood, behavior and even an individual’s personality. Some of the more common psychiatric symptoms of Alzheimer’s disease include:

  • Aggression and angry outbursts
  • Depression
  • Hallucinations and their accompanying feelings of fear and agitation (occurs in mid to late-stages of the disease)
  • Hiding possessions
  • Irritability and restlessness
  • Loss of interest in social activities and hobbies
  • Mood swings (loss of control over emotions).


Alzheimer Foundation of America. (n.d.) About Alzheimer’s: Symptoms. Retrieved April 26, 2010, from

Alzheimer Society of Canada. (n.d.) The effects of Alzheimer’s disease. Retrieved April 26, 2010, from

Mayo Clinic. (2009). Symptoms. Retrieved April 26, 2010, from

 Posted on : June 14, 2014