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Alzheimer's Disease Signs and Symptoms

February 16, 2023Neelem Sheikh

Everyone’s experience living with Alzheimer’s disease is unique. Alzheimer’s is a highly complex disease, and its pathology and disease mechanisms can affect each individual differently. Consequently, a wide range of possible symptoms can arise throughout the disease course.

This article will cover some of the most common Alzheimer’s disease signs and symptoms throughout the disease continuum.

How Alzheimer’s Affects the Brain

To understand why symptoms such as memory loss and behavioral changes arise, it’s important to understand how Alzheimer’s disease affects the structures of the brain. The human brain comprises around 86 billion neurons that process and transmit information through chemical and electrical signals. As plaques and tangles from Alzheimer’s disease spread through various brain regions, these neurons die. Because neurons do not divide, regenerate, or renew themselves, they are not replaced.

In the early stages, Alzheimer’s disease causes damage to brain regions that are essential for learning and memory as well as thinking and planning. This is why memory loss is often one of the first reported symptoms in people living with Alzheimer’s disease. 

As Alzheimer’s disease progresses and plaques and tangles become more widespread, regions involved in speech, articulation, and visual perception are affected. Alzheimer’s disease can also damage structures in the cerebral cortex, such as the frontal lobe, which is involved in focus, attention, decision-making, speech, impulse control, social behavior, and other aspects of behavior and personality. In advanced Alzheimer’s disease, many brain regions are affected, including those involved in movement and motor control.

Alzheimer’s Disease Signs and Symptoms

As a result of the damage in various brain regions, people living with Alzheimer’s disease typically experience a range of cognitive, functional, behavioral, and psychological symptoms throughout the disease continuum. 

Alzheimer’s disease signs and symptoms throughout the disease course may include the following:

Alzheimer’s Disease Signs and Symptoms



Memory Loss

  • Forgetting recently learned information

  • Repeating the same question

  • Forgetting birthdays or other important dates and events (and being unable to remember them later)

  • Relying more and more on memory aids

Impaired Planning

  • Forgetting the rules or steps to a favorite game 

  • Difficulty driving to a familiar place

  • Struggling to cook a familiar recipe

Impaired Visual Perception

  • Difficulty visualizing and interpreting surroundings

  • Difficulty judging distances (e.g., when driving)

Impaired Spatial Memory

  • Difficulty recalling the location of objects, places, or events

  • Misplacing objects or placing them in abnormal locations

  • Forgetting where the light switch is in the bathroom

Changes in Speech

  • Difficulty recalling words

  • Difficulty finding the right word to use

  • Pausing when speaking

  • Struggling to finish a sentence

Mood Disturbances

  • Anxiety

  • Depression

  • Confusion 

  • Irritability 

  • Agitation

  • Paranoia 

  • Fear 

Sleep Disturbances

  • Sleep fragmentation

  • Insomnia

  • Excessive daytime sleepiness

  • Sundowning (confusion, agitation, anxiety, irritability, or disorientation that occurs in the late afternoon and early evening)

Behavioral and Personality Changes

  • Aggression

  • Losing interest in previously enjoyed activities

  • Social withdrawal

  • Apathy

  • Insensitivity to others

  • Delusions

  • Hallucinations

  • Wandering 

  • Pacing

  • Unusual sexual behavior

Impaired Movement and Motor Function

  • Issues with fine motor coordination

  • Stiffness and rigidity of the muscles

  • Loss of balance or coordination

  • Shuffling or dragging the feet when walking

  • Difficulty standing from a chair

  • Losing physical abilities, such as walking, sitting, and swallowing (typically seen in severe Alzheimer’s)

  • Loss of bowel or bladder control (typically seen in severe Alzheimer’s)

  • Inability to independently complete activities such as eating, bathing, dressing, and toileting (typically seen in severe Alzheimer’s)

For more information on Alzheimer’s disease, listen to this podcast sponsored by Altoida: What is Alzheimer’s Disease?

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