How Stroke Affects Speech

Strokes affect each individual differently depending on the extent of the damage and the area of the brain affected. Damage to one of the language areas of the brain will often result in aphasia. Aphasia is a communication impairment that impacts identity and relationships because of difficulties speaking, understanding, reading, and writing (Kagan & Simmons-Mackie, 2013).

The left hemisphere of the brain controls the right side of the body and the right hemisphere of the brain controls the left side of the body. Damage to the different hemispheres of the brain will result in different impairments. Based on location of the stroke, the following may be affected.

Left  Hemisphere:

  • Speaking
  • Reading
  • Writing
  • Listening
  • Grammar
  • Number/Math skills
  • Computation skills
  • Analyzing information
  • Reasoning
  • Logic
  • Sequential thinking
  • Time awareness

Right Hemisphere:

  • Organizing information
  • Abstract meaning
  • Context
  • Spatial relationships
  • Visual information
  • Face recognition
  • Intuition
  • Emotion
  • Imagination
  • Detecting motion
  • Music and art awareness

Communication Challenges

Aphasia can affect both expressive and receptive language as well as cognition. It is important to note however, that aphasia does not affect intellect. Below is a list of communication challenges a person with aphasia may experience.

Expressive Language

  • Difficulty with word finding
  • Slurred or unintelligible speech
  • Difficulty writing
  • Trouble using numbers or doing math

Receptive Language

  • Trouble understanding spoken language
  • Trouble following directions
  • Difficulty reading

Cognitive Problems

  • Difficulty maintaining attention
  • Memory loss
  • Trouble with reasoning or problem solving
  • Difficulty making judgments
  • Disorganization
  • Disorientation
  • Slow processing speed

In addition to aphasia, a stroke survivor may be diagnosed with apraxia of speech and/or dysarthria.   

Apraxia of Speech

Difficulty initiating and executing voluntary movement patterns necessary to produce speech when there is no paralysis or weakness of speech muscles. Apraxia of speech is characterized by:

  • Difficulty producing the desired speech sound
  • Difficulty using the correct rhythm and rate of speaking


A speech disorder caused by muscle weakness. It can make talking clearly very hard. Dysarthria is characterized by:

  • Slurred or mumbled speech
  • Effortful/slow speech
  • Limited movement in tongue, lips, and jaw
  • Robotic or choppy sounding speech
  • Hoarseness or breathiness


Caregiver Help

Meet Your Healthcare Team

What to Ask The Doctor About Aphasia

Preparing for Life After the Hospital

Rehabilitation & Therapy

How Stroke Affects Speech

Communication Tips

Caregiver Support Group Finder