The Long-Term Effects of a Temporal Lobe Stroke

A stroke is a potentially life-threatening health condition that occurs when the arteries leading to and within the brain are blocked or ruptured - causing a lack of blood oxygen and nutrients. It is the leading cause of long-term disability in the United States and the fifth cause of death. One type of stroke, which can lead to long-term health effects, is temporal lobe stroke.

Overview

The brain is an extremely complex organ that controls many of the body's core functions. It gets its blood supply from several different blood vessels that follow a 'map' to provide oxygen and nutrient-rich blood to specific regions.

The regions of the brain each have certain functions and are responsible for functions including physical movement, sensation, speech, thinking skills, emotions - just about everything the body does. If a stroke occurs and blood can't reach a specific region of the brain, then the particular function controlled by that part of the brain won't work as it should.

A stroke can produce a variety of symptoms that correspond to which part of the brain is affected. The main regions of the brain include the brainstem, the cerebellum, and the four lobes on each side (frontal lobes, temporal lobes, parietal lobes, and occipital lobes).

Causes

A stroke occurs when blood flow to a region of the brain is interrupted. When that happens, part of the brain cannot get the oxygen and nutrients it needs, which ultimately causes damage to that area of the brain.

A stroke can be caused either by a blood clot obstructing the flow of blood to the brain (​ischemic stroke) or by a blood vessel leaking or rupturing and preventing blood flow to the brain (hemorrhagic stroke). A TIA (transient ischemic attack), or "mini-stroke," is caused by a temporary interruption in blood flow that resolves without causing permanent damage.​​

Long-Term Effects

There are numerous effects of a temporal lobe stroke, ranging from difficulty speaking to hearing loss to much more.

Speech

The temporal lobe is one of the speech centers of the brain. It is specifically the dominant temporal lobe (the side opposite your dominant hand) that controls speech, not both temporal lobes.

A temporal lobe stroke often causes a type of speech problem called Wernicke's aphasia, which is characterized by trouble making sense of spoken language. It can also include:

• Pure word deafness
• Transcortical aphasia
• Anomic aphasia—difficulty retrieving names for things and people

Hearing

The temporal lobe is the main region of the brain that controls the sensation of hearing. Usually, hearing loss is mild after one temporal lobe is affected by a stroke. But when both temporal lobes are affected the result might be complete deafness. This is very rare. Other hearing-related effects include:

• Auditory agnosia—Difficulty recognizing combinations of sounds, such as songs, musical tones, and complex conversations
• Auditory verbal agnosia—Similar to pure word deafness (see above)
• Auditory illusions—Aberrant perception of normal sounds so that they feel unusual, strange, repeated, or loud
• Auditory hallucinations—One hears sounds that are not there. These sounds may be very complex (the sound of a song being played on the radio) or very simple (whistles or sirens). People may or may not realize that these sounds represent a hallucination. In some cases, auditory hallucinations may be accompanied by visual ones.

Memory, Emotion, and Behavior

The temporal lobe, along with the frontal lobe, is responsible for emotions and personality. There are a number of stroke-induced personality changes; the following are most closely linked with the temporal lobe.

• Loss of short- or long-term memory
• Fits of rage
• Violent or aggressive behavior
• Placidity
• Lack of interest
• Abnormally enhanced sexuality

Seizures

Not all strokes can cause seizures, but temporal lobe strokes are among the stroke types most closely associated with stroke-induced seizures and post-stroke epilepsy.

Other rare long-term effects of a temporal lobe stroke can include:

• Vertigo—A type of balance problem
• Abnormal perception of time—A feeling that time stands still or goes by extremely quickly. People might intermittently lose the sense of what year, season, or month it is.
• Disturbances of smell and taste