The temporal lobe is one of the four major lobes of the cerebral cortex. It is located beneath the lateral fissure and is involved in processing sensory input, visual and auditory memory, language comprehension, and emotional association. The temporal lobe contains several functional areas including Heschl's gyrus, the superior temporal gyrus, middle temporal gyrus, inferior temporal gyrus, fusiform gyrus, hippocampus, amygdala, and dentate gyrus. Lesions or damage to different areas of the temporal lobe can cause symptoms like aphasia, temporal lobe epilepsy, Klüver–Bucy syndrome, memory loss from infarcts, or psychotic symptoms from tumors.
2. Temporal Lobe
• One of the four major lobes of cerebral cortex.
• Located beneath lateral fissure
• Processing sensory input into derived meaning
• Appropriate retention of visual memory
• Language comprehension
• Emotional association
• Seat of human para-psychological and psychic
abilities
13. Symptoms of Temporal Lobe Lesions
1. Disturbance of Auditory Sensation and perception
2. Disturbance of selective attention of auditory and visual input
3. Disorders of visual perception
4. Impaired organization and categorization of verbal material
5. Disturbance of language comprehension
6. Impaired long term memory
7. Altered personality and affective behavior
8. Altered sexual behavior
-Kolb & Wishaw (1990)
14. • Left superior temporal gyrus difficulty in discriminating
speech
• Right superior temporal gyrus inability to discriminate
melodies and produce prosody
• Inferior temporal gyrus inability to recognize objects, called
Visual agnosia
• Fusiform gyrus inability to recognize face, called
Prosopagnosia (face blindness)
15. Organization & Categorization
• Left temporal lobe lobotomies lead to impairment in the ability to
categorize words or pictures of objects
• Posterior lesions lead to a difficulty in recognizing specific word
categories
Language Comprehension
• Stimuli can be interpreted in different ways depending on the
context
Example: Fall - the season or a tumble
16. Memory
• Antero-grade Amnesia
– Amnesia for events after bilateral removal of the medial
temporal lobes
• Infero-temporal Cortex
– Conscious recall of information
• Left temporal lobe
– Verbal memory
• Right temporal lobe
– Impaired recall of nonverbal material
17. Affect
• Stimulation of anterior and medial temporal cortex produces feelings
of fear
Temporal Lobe Personality
(Geschwind syndrome)
– Personality that overemphasizes trivial and petty details of life
– Pedantic speech (an overly formal speaking style inappropriate to
the conversational setting)
– Egocentricity (preoccupation with one’s own internal world)
– Perseveration
– Paranoia
– Preoccupation with religion
– Proneness to aggression
21. Conduction Aphasia
• Affect Arcuate Fasciculus which connects Wernicke’s &
Broca’s area
• Speech & writing are impaired as in wernicke’s aphasia
• Repetition is severely impaired
• Comprehension of spoken & written material well preserved
- Lishman’s Organic Psychiatry
23. 2. TEMPORAL LOBE EPILEPSY
• Temporal lobe epilepsy (TLE) was defined in 1985 by the
International League Against Epilepsy (ILAE) as a condition
characterized by recurrent unprovoked seizures originating
from the medial (Hippocampus, Para-hippocampal gyrus,
Amygdala) or lateral temporal lobe (Neocortex)
• Begins in late childhood or early adulthood
• Most common of anatomically defined syndromes (around
60%)
• Most varied and complex auras
• Resembles with symptoms of psychiatric disorder
- Lishman’s Organic Psychiatry
24. CAUSES
• Hippocampus sclerosis a.k.a. Mesial temporal sclerosis or
Ammon’s horn sclerosis
• Childhood febrile convulsions
• Tumors
• Cortical dysplasia 2ry to encephalitis and meningitis
• Head injury or vessel malformation
• Trauma
• Congenital brain malformations
- Lishman’s Organic Psychiatry
25. Types- 1. Simple
2. Complex
Auras-
1.Epigastric aura
2.Cephalic aura
3.Affective aura (Anxiety, Fear)
Ictal- Oral automatism
Manual automatism
Speech automatism / Vocalization
Illusions and Hallucinations
Experiential phenomenon
Affective Features
Non convulsive status epilepticus
- Lishman’s Organic Psychiatry
26.
27. 3. Klüver–Bucy syndrome
Klüver–Bucy syndrome is a syndrome resulting from bilateral
lesions of the anterior temporal lobe including amygdaloid nucleus
1. Amnesia
2. Docility
3. Hyperphagia / Dietary changes
4. Hyper-orality
5. Hyper-sexuality
6. Visual agnosia
7. Others- Hyper-metamorphosis, diminished emotional affect
- From Wikipedia, Free encyclopedia
28. 4.Temporal Lobe Infarct
Middle cerebral artery-
• Wernicke’s aphasia
• Conduction aphasia
• With or without sensory-motor deficit
Posterior cerebral artery-
• Recent memory loss
29. 5. Temporal Lobe Tumors
• Patients with temporal lobe tumors experience psychiatric,
behavioral, or personality changes
• Patients with tumors of the temporal lobe who have temporal lobe
seizures often have seizure-associated schizophrenia-like
psychotic symptoms
• Symptoms include-Auditory hallucinations and atypical dream-
like episodes, depersonalization, blanking-out spells
• May present with depression and frontal lobe–like apathy &
irritability or with features suggesting hypomania or mania,
• Personality changes commonly occur and may be one of the
earliest indications of an undiagnosed temporal lobe tumor