Seen from either side, the brain looks like a boxing glove, with a thumb pointing in the same direction as the gaze and a downward-facing palm. On this picture, the two temporal lobes are the thumb areas. The brain's temporal lobes, which are located below and behind the brain's frontal lobes, maintain important cognitive and emotional functions, including emotional processing, memory storage, language and speech processing and facial and shape recognition. Injuries to the lobes will produce problems in these areas.
Difficulties Recognizing and Remembering Faces
The amygdala, which processes emotional stimuli, and the hippocampus, which is responsible for short- and intermediate-term memory, are two temporal lobe areas crucial to face recognition and memory. Difficulties recognizing or remembering facial expressions can be a sign of damage to one of these two areas.
While many conditions can cause damage to the amygdala and the hippocampus, something as seemingly innocent as binge drinking is a significant predictor, according to a study published in the November 2009 issue of "Alcoholism: Clinical & Experimental Research." The San Diego research team scanned the brains of 15 men recovering from an alcohol problem and 15 men who rarely drank alcohol and found a decreased activation in the temporal lobe areas in response to facial expressions in the first group.
Short-Term Memory Problems
Memory problems can be a sign of damage to the hippocampus in the medial temporal lobe areas. The hippocampus is involved in storage-based short-term memory and the transformation of short-term memories into long-term memories. Damages can occur as a result of oxygen-deprivation, age-related dementia, a viral infection caused by herpes simplex viruses HSV1 or HSV2, bacterial infections and psychotic and neurotic disorders such as schizophrenia and major depression.
Injuries specific to the hippocampal areas typically affect the ability to store new experiences, though sometimes hippocampal injuries have no detrimental effect, says University of Liverpool psychologist Juliet Holdstock in "Science Daily."
Epilepsy
Epilepsy is a neurological disorder consisting of recurrent seizures. As many seizures begin as hyper-excitements of neurons in the temporal lobe that spread to other parts of the brain, epilepsy can be a symptom of temporal lobe damage. There is a strong correlation between infection with the human herpes virus 6, or HHV-6, and a common form of epilepsy known as "mesial temporal lobe epilepsy," reports an international research team in a 2007 issue of "PLoS Med."
Up to 90 percent of the general population becomes infected with HHV-6 before they reach middle age. After primary infection, the virus normally stays dormant in the central nervous system. Seizures occur when the virus activates or reactivates in the brain.
Language Problems and Speech Irregularities
As language is typically processed in the left temporal lobe, language problems and speech irregularities can be a symptom of left temporal lobe injury. Speech irregularities may result from over-sized temporal lobes, according to a study published in the July 24, 2001 issue of "Neurology." The research team scanned the brains of 16 adults with persistent developmental stuttering and 16 controls and found that the first group had significantly enlarged temporal lobes. This suggests that neuron over-activity rather than social anxiety is a trigger of speech irregularities.
References
- "Alcoholism: Clinical & Experimental Research "; Alcoholism and Dampened Temporal Limbic Activation to Emotional Faces; Marinkovic, et al.; November 2009
- Science Daily: Memory Function Varies After Damage To Key Area Of The Brain
- "PLoS Med"; Association of human herpesvirus- 6B with mesial temporal lobe epilepsy; Fotheringham, et al.; May 2007
- "Neurology"; Anomalous anatomy of speech--language areas in adults with persistent developmental stuttering; Foundas, et al.; July 2001
- "The Temporal Lobe and Limbic System"; Pierre Gloor; 1997
