Dr .Virinchi Sharma

1. TEMPORAL
LOBE
PRESENTOR:- DR VIRINCHI
SHARMA
MODERATOR:-
Dr. V S RAJ
1

2. 0VERVIEW
• ANATOMY(parts)
• FUNCTIONAL AREAS
• LOOPS & PATHWAYS
• FUNCTIONS
• DISORDERS 2

3. • The Temporal lobes are one of the most
heterogeneous regions of the Neocortex.
• Input for the Limbic and Para-Limbic cortex.
• This is the lobe that is credited with being the seat
of human para-Psychological and Psychic
abilities!
• The temporal lobe, Is considered in its broadest
context, links the present sensory and emotional
experience of our world
3

4. M Y
A T O
N
A OF B E
L LO
R A
P O
T E M 4

5. • The temporal lobes, are the part of the cerebral cortex in
the left and right hemispheres of the brain lying inside the
temples.
• Directionally, the temporal lobes are anterior to the occipital lobes,
inferior to the frontal lobes and parietal lobes, and lateral to the
Fissure of Sylvius, also known the lateral sulcus 5

6. • SUPERIOR AND INFERIOR
TEMPORAL SULCI DIVIDE
TEMPORAL LOBE INTO 3 LOBES
• SUPERIOR TEMPORAL LOBE
• MIDDLE TEMPORAL LOBE
• INFERIOR TEMPORAL LOBE
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7. 7

8. SUPERIOR TEMPORAL
LOBE
• involves areas 41,42,22
• Primary auditory area (area 41)
• On the left side of the brain this area helps
with generation and understanding of
individual words.
• On the right side of the brain it helps tell
the difference between melody, pitch, and
sound intensity
8

9. MIDDLE TEMPORAL LOBE
The region encompasses most of the lateral
temporal cortex, a region believed to play a
part in auditory processing and language.
• Language function is left lateralized in most
individuals.
• Brodmann area 21.
9

10. INFERIOR TEMPORAL
LOBE
• It refers to a subdivision of the
cytoarchitecturally defined temporal
region of cerebral cortex. In the human
it corresponds approximately to the
inferior temporal gyrus.
• Brodmann area 20.
• The region encompasses most of the
ventral temporal cortex, a region
believed to play a part in high-level
visual processing and recognition 10

11. MEDIAL PART OF
TEMPORAL LOBE
• The medial temporal lobe comprises the
hippocampus and amygdala, as well as the
entorhinal, perirhinal and 11

12. Amygdala
12

13. Amygdala
• The fear & flight response
• Inputs: The association areas of visual, auditory, and
somato sensory cortices are the main inputs to the
amygdala.
• Outputs: The main outputs of the amygdala are to the
hypothalamus and brainstem autonomic centers,
including the vagal nuclei and the sympathetic
neurons.
• The amygdala is also involved with mood and the
conscious emotional response to an event
• The amygdala is also extensively interconnected with
frontal cortex, medio dorsal thalamus, and the medial
striatum. 13

14. • The deep group, which
includes the lateral, basal,
accessory basal nucleic
• Func: collects input from
sensory cortex.
• The more dorsal group,
which includes the central &
medial nuclei
• Func: receives projections
from the deep group and
sends the signal out to
autonomic centers.
14

15. • The amygdala is the heart of the emotional
system. It processes and interprets all sensory
data.
• It modulates the flow of emotional
information between the cerebral cortex and
the hypothalamus, and in doing that, it
modulates autonomic, endocrine, and
affective responses.
• Lesions in amygdala lead to-- agitation,
irritability, anxiety, mood disorders,
paranoia, and psychosis.
15

16. 16

17. The Hippocampus
• The hippocampus is a scrolled structure
located in the medial temporal lobe.
• The hippocampus can be divided into at least
five different areas.
• The dentate gyrus is the dense dark layer of
cells at the "tip" of the hippocampus. Areas
CA3 and CA1 are more diffuse; the small
CA2 is hard to distinguish between them.
(CA stands for cornu ammonis, from its ram's
horn shape.)
• The subiculum sits at the base of the
hippocampus, and is continuous with
entorhinal cortex, which is part of the 17

18. 18

19. FUNCTIONAL
AREAS OF
TEMPORAL LOBE
19

20. • AUDITORY – primary & Association
• OLFACTORY - primary & Association
• VISUAL (Recognition & association)
• MEMORY
• EMOTIONAL & SOCIAL
• Link past and present sensory and
emotional experiences into a 20

21. LANGUAGE &
COMPREHENSION
• LANGUAGE AREAS
• A specialized integration area called Wernicke's area is
found in the posterior temporal lobe of one hemisphere
(usually the left). Commonly called the "speech area, "
Wernicke's area surrounds and encompasses part of the
auditory association area.
• AFFECTIVE LANGUAGE AREAS
• Affective language areas involved in the nonverbal
emotional components of language - appear to be present
in the hemisphere opposite Brocas's and Wernickes's
areas.
• These "mirror images" allow the lilt of tone of our voice
and our gestures to express our emotions when we speak,
and permit us to comprehend the emotional content of
what we hear. 21
• Lesions to this area result in aprosodia, a condition in

22. AUDITORY SENSES
• PRIMARY AUDITORY AREA (area 41)
Essential to detect changes in
frequency , & to know the direction
from which sounds originate.
• AUDITORY ASSOCIATION AREA
(area 42)
• HIGHER AUDITORY ASSOCIATION 22

23. 23

24. VISUAL SENSES
• Processing of our
recognition of objects
occurs in a path on the
lower, dorsal stream in
the temporal lobe; here
you find areas sensitive to
faces vs. objects,
• Area MT (right) performs
processing on motion.
Subjects without an area
MT describe seeing
motion as discontinuous
24
pictures – eg.having to

25. OLFACTORY SENSES
The rightmost green
spots are the location in
cortex where smell is
processed.
25

26. GUSTATORY SENSES
• The sensation of
taste is processed in
insular cortex
26

27. connections of the Temporal Lobes
• Five main types:
• Hierarchical sensory pathway
• Dorsal auditory pathway
• Polymodal pathway
• Medial (mesial) temporal pathway
• Frontal lobe projection

28. • Hierarchical sensory pathway
• connections from
• primary(sensory neuron) and secondary auditory
and visual
cortical
• through the lateral temporal cortex
• terminate in the temporal pole

30. • visual travels inferior temporal gyrus
•
• auditory travels e suprior temporal gyrus
• Major destinations:
• amygdala and hippocampus
• This results in the integration of information into:
memory, retrieval of stored information,
emotional tone
• Ultimate effect
stimulus recognition
• The familiar conscious experience of knowing,
assimilating, and feeling

31. • Dorsal auditory pathway
• Forms important functional connections with
the posterior parietal cortex
• Enables location of sounds in space
• Promotes orienting and initiation of
movements relative to sound location

33. Polymodal Pathway
• connections emerging from the auditory and
visual hierarchical pathways
• Directed towards the neurons enfolded within
the superior temporal sulcus
• Polymodal nature of neurons
• Assigns stimuli to specific category of classes,
linked to and can be retrieved by memory

35. • Medial Temporal Projection
• Projections from auditory and visual areas into the
limbic regions
• E.g., amygdala and hippocampus
• Directions of projections
Peripheral cortex entorhinalcortex
amygdala/hippocampus
• Perforant pathway
• forms the main projection to thehippocampus
• Damage in this region severely affects memory
formation

37. • Frontal-lobe Projection
• Neurons from the temporal lobe have strong
connections with the frontal lobe
• Posterior temporal cortex
• Projects to the dorsolateral prefrontal cortex
• anterior temporal cortex
• Projects to the orbital frontal cortex
• Damage leads to terrible life decisions

39. DISORDERS OF
TEMPORAL LOBE
39

40. 8 principal symptoms of
temporal lobe damage:
• Disturbance of auditory sensation and
perception
• Disturbance of selective attention of
auditory and visual input
• Disorders of visual perception
• Impaired organization and categorization of
verbal material
• Disturbance of language comprehension
• Impaired long-term memory
• Altered personality and affective behaviour
• Altered sexual behaviour 40

41. Manifestations of temporal lobe
lesions
• Disorders of auditory perception:
– Lesions of the left superior temporal gyrus produce
problems of speech perception with difficulty in
discriminating speech and the temporal order of sounds is
impaired.
• Lesions of the right superior temporal gyrus can
produce disorders of perception of music with inability to
discriminate melodies and produce prosody
• The inferior temporal cortex is responsible for visual
perception and lesions produce inability to recognise faces,
called prosopagnosia.
• There may be disturbance of visual and auditory input
selection. This presents as impairment of short term memory,
41

42. disorders of memory
• The medial and inferior temporal cortex and hippocampus are
responsible for memory.
• There is complete anterograde amnesia following bilateral
removal of medial temporal lobes, including hippocampus &
amygdala.
• There is difficulty recalling information.
• The left side is responsible for verbal material and the right for
non-verbal memory such as faces, tunes and drawings.
42

43. • temporal lobe personality. There is
egocentricity, pedantic speech, perseveration
of speech, paranoia, religious preoccupations
and a tendency to aggressive outbursts,
especially after right temporal lobectomy.
• temporal lobe lesions can present with visual
field defects in the form of superior quadrant
loss, sometimes called the "pie in the sky
defect."
• Stroke normally reduces libido but temporal 43

44. APHASIA
• Any disturbance in the comprehension or
expression of language caused by a brain
lesion.
• NONFLUENT APHASIA, i.e. in lesion to
Broca's area results in slow speech, difficulty
in choosing words, or use of words that only
approximate the correct word.e.g., a person
may say "tssair" when asked to identify a
picture of a chair.
• A lesion to Wernicke's area may result in
FLUENT APHASIA, in which a person speaks
normally, and sometimes excessively, but uses
jargon and invented words, that make little 44

45. Kluver-Bucy syndrome
 Kluver-Bucy syndrome results due to a bilateral
destruction of the amygdaloid body and inferior
temporal cortex.
 It is characterized by
Visual agnosia,
Placidity,
Hypermetamorphosis,
Hyperorality
Hypersexuality.
 causes: cerebral trauma; infections including
herpes and other encephalitides; Alzheimer's
disease and other dementias; Niemann-Pick disease 45
and cerebrovascular disease.

46. Diseases of the Hippocampus
• The hippocampus is
particularly vulnerable to
several disease processes,
including ischemia, which
is any obstruction of blood
flow or oxygen deprivation,
Alzheimer's disease,
and epilepsy.
• These diseases selectively
attack CA1, which
effectively cuts through the
hippocampal circuit.
46

47. 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
OR LATERAL TEMPORAL LOBE.
LATERAL TEMPORAL LOBE EPILEPSY : ARISES IN THE
NEOCORTEX
MESIAL TEMPORAL LOBE EPILEPSY:HIPPOCAMPUS,
PARAHIPPOCAMPAL GYRUS AMYGDALA
47

48. cAuSES
• Hereditary
• Febrile sezuires
• Brain tumors
• spinal meningitis,
• encephalitis,
• head injury or blood vessel malformations
• Trauma
• congenital brain malformations
• Alcohol withdrawl
• Sleep deprivation
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49. SYMPTOM
• S
Seizures usually simple partial but can be complex
partial seizures also
• Duration is one to two minutes
• Auras
• Motionless staring
• Anxiety
• Emergent past memories
• Spiritual religious experience
• Most common type comprising 70percent of
seizures with 1.5%of population world wide
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50. TREATMEnT
• Antiepilectic drugs
• Surgical procedures
50

51. cVA---TEMPORAL LOBE
• Middle cerebral artery in farct:
– Aphasia or non-dominant hemisphere findings
depending on the side.
– “Partial” middle cerebral artery syndromes, almost
always of embolic origin, may include a) sensorimotor
paresis with little aphasia b) conduction aphasia c)
Wernicke’s aphasia without hemiparesis.
– Wernicke's aphasia, caused most often by occlusion of
the lower division of the MCA bifurcation or one of its
branches. Patients with Wernicke's aphasia vocalize
smoothly and with expression, but they demonstrate
paraphasias or speech with distorted phonetic structure,
word substitution, and additional prefixes and suffixes.
– The infarct responsible for a classic Wernicke's aphasia
includes the dominant posterior temporal, inferior
parietal, and lateral temporo-occipital regions.
51
• Posterior cerebral artery syndrome:

52. TEMPORAL LOBE ABScESS
• Brain abscess is a
newly formed cavity in
brain tissue, filled with
pus.
• Mastoiditis causes
temporal lobe abscess.
• Hematogenous
abscesses are often
multiple.
52

53. TEMPORAL LOBE
TUMORS
• As many as 50 to 55 percent of patients
with temporal lobe tumors experience
psychiatric, behavioral, or personality
changes
• Psychopathology related to temporal lobe
tumors can be ictal, that is, seizure
associated, or interictal, completely
unrelated to seizure activity.
• Patients with tumors of the temporal lobe
who have temporal lobe seizures often
have seizure-associated schizophrenia-like 53

54. SYMPTOMS INCLUDE
• Auditory hallucinations and atypical
dream-like episodes, depersonalization,
blanking-out spells, and dazed feelings
• Patients with temporal lobe seizures may
present with depression and frontal lobe–
like apathy and 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 54

55. Thank you
Thank u…….
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