higher cortex function

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HIGHER CORTEX FUNCTIONS, HIGHER CORTEX FUNCTIONS, DEFEAT OF SEPARATED BRAIN DEFEAT OF SEPARATED BRAIN LOBES. LOBES.

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Page 1: Higher cortex function

HIGHER CORTEX FUNCTIONS, HIGHER CORTEX FUNCTIONS,

DEFEAT OF SEPARATED BRAIN DEFEAT OF SEPARATED BRAIN LOBES.LOBES.

Page 2: Higher cortex function

Higher cortex functions are inherent Higher cortex functions are inherent only to the cortex of large brain of only to the cortex of large brain of

manman..They are They are speech, praxis, gnosisspeech, praxis, gnosis

and etc and etc

These are located in a left These are located in a left hemisphere (at people hemisphere (at people with leading right arm)with leading right arm)

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Speech Speech There are There are expressiveexpressive and and impressive impressive

parts ofparts of speech. speech. By an By an expressiveexpressive speech we express speech we express

opinions, opinions, impressiveimpressive – understand – understand heard. In babies the heard. In babies the impressive impressive speech develops fspeech develops firstlyirstly..

Speech disorders Speech disorders – – aphasia, aphasia, dysartria or anartria, mutism, dysartria or anartria, mutism, undevelopment of undevelopment of speech - alalia.speech - alalia.

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AphasiaAphasia Aphasia is a partial or complete loss of Aphasia is a partial or complete loss of

the ability to express or understand the ability to express or understand spoken or written spoken or written speechspeech because of because of damage the damage the speechspeech areas of the brain. areas of the brain.

The loss of motor or sensory function of The loss of motor or sensory function of speech is named speech is named aphasiaaphasia (from greec. (from greec. phases—speechphases—speech). ).

Due to the classification Due to the classification there arethere are motor motor sensory sensory amnesicamnesic total aphasiatotal aphasia

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Motor aphasia - Motor aphasia - Broca's aphasiaBroca's aphasia The center of expressive (motor) speechThe center of expressive (motor) speech (the (the

part of motion analyzer, related to the area for part of motion analyzer, related to the area for motions of tongue, lips, larynges motions of tongue, lips, larynges is located in the is located in the back region of lower frontal gyrusback region of lower frontal gyrus (the Broka (the Broka center) in center) in a left hemisphere (at people with a left hemisphere (at people with dominant right arm).dominant right arm).

People suffering from damage of this area may People suffering from damage of this area may have a condition called have a condition called Broca's aphasiaBroca's aphasia (sometimes (sometimes known as known as expressive aphasiaexpressive aphasia, , motor aphasiamotor aphasia), ), which makes them unable to create which makes them unable to create grammatically-complex sentences: their speech grammatically-complex sentences: their speech is often described as is often described as telegraphictelegraphic and very often and very often there is missing of storages in speech.there is missing of storages in speech.

Very often there is Very often there is speech embolusspeech embolus – repeating – repeating the same syllable.the same syllable.

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Broca's area is named after the 19th Broca's area is named after the 19th century physician century physician Paul BrocaPaul Broca

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Motor aphasiaMotor aphasia A patient A patient can notcan not make articulation motions on make articulation motions on

the taskthe task, , can notcan not reproduce motion exploringreproduce motion exploring. It . It results in replacement of one articulations by results in replacement of one articulations by other, to replacement of sounds (in place of “k” other, to replacement of sounds (in place of “k” -“h” or “t” is pronounced, in place of “l”—“n”). It -“h” or “t” is pronounced, in place of “l”—“n”). It results in distortion of semantic value of words. results in distortion of semantic value of words. Speech as difficult functional system Speech as difficult functional system disintegratesdisintegrates..

For example, in the following passage, a Broca's For example, in the following passage, a Broca's aphasic patient is trying to explain how he came aphasic patient is trying to explain how he came to the hospital for dental surgery.to the hospital for dental surgery.

"Yes... ah... Monday... er... Dad and Peter H... "Yes... ah... Monday... er... Dad and Peter H... (his own name), and Dad.... er... hospital... and (his own name), and Dad.... er... hospital... and ah... Wednesday... Wednesday, nine o'clock... ah... Wednesday... Wednesday, nine o'clock... and oh... Thursday... ten o'clock, ah doctors... and oh... Thursday... ten o'clock, ah doctors... two... an' doctors... and er... teeth... yah."two... an' doctors... and er... teeth... yah."

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Sensory aphasia - Sensory aphasia - Wernicke's aphasiaWernicke's aphasia The specialized region of analysis and The specialized region of analysis and

synthesis of signals (that is impressive synthesis of signals (that is impressive speech) is concentrated near the auditory speech) is concentrated near the auditory analyzer, in the back department of analyzer, in the back department of overhead temporal gyrus overhead temporal gyrus ((the Vernike the Vernike centercenter).).

In case of damage of this center a patient In case of damage of this center a patient loses ability to know sounds and loses ability to know sounds and understand words as other people, soon understand words as other people, soon as himself. The motor function of speech as himself. The motor function of speech is saved, however, patient’s speech is not is saved, however, patient’s speech is not understanding. understanding.

The contact with such sick in heavy case is The contact with such sick in heavy case is extraordinarily difficult. extraordinarily difficult.

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Amnesic aphasiaAmnesic aphasia The Amnesic aphasia The Amnesic aphasia arises up at the arises up at the

defeat of defeat of temporal-parietal-occipital temporal-parietal-occipital regionregion and is characterized by forgetting and is characterized by forgetting of nouns and difficulties in the use of of nouns and difficulties in the use of difficult logic-grammatical structures. difficult logic-grammatical structures.

Patients Patients can freely socializecan freely socialize with people, with people, their their speech is clear, though poor by speech is clear, though poor by nounsnouns. Hiding the bug, patients replace . Hiding the bug, patients replace the names of objects by their description: the names of objects by their description: a pen – *it is to write*, a glass – *it is to a pen – *it is to write*, a glass – *it is to drink*. It is usually enough is to prompt drink*. It is usually enough is to prompt the first syllable of the word, forgotten by the first syllable of the word, forgotten by the patients, that it correctly made off it. the patients, that it correctly made off it.

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AlexiaAlexia (inability to read) arises up at (inability to read) arises up at processes in an angular gyrus processes in an angular gyrus (temporal lobe)(temporal lobe)

AgraphiaAgraphia (inability to write) arises (inability to write) arises up at the defeat of back region of up at the defeat of back region of middle frontal gyrus.middle frontal gyrus.

AcalculiaAcalculia (violation of account) (violation of account) comes at the defeat of temporal-comes at the defeat of temporal-parietal-occipital regionparietal-occipital region

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AlexiaAlexiaAgraphiaAgraphia AcalculiaAcalculia

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Other types of speech disordersOther types of speech disorders It should be remembered that disorders of It should be remembered that disorders of

speech can appear at other defeats of the speech can appear at other defeats of the nervous system.nervous system.

At paresis or paralysis of muscles of At paresis or paralysis of muscles of articulation (tongue), speech becomes articulation (tongue), speech becomes illegible, indistinct illegible, indistinct (disartria)(disartria)..

In heavy case the speech becomes In heavy case the speech becomes impossible impossible (anartria)(anartria). .

At parkinsonismAt parkinsonism speech suffers also, it is speech suffers also, it is done poor expressed, done poor expressed, monotonousmonotonous. The . The diseases of diseases of cerebellumcerebellum, attended with , attended with ataxia, are characterized by the ataxia, are characterized by the scanned scanned speechspeech. Speech at people . Speech at people losing earlosing ear in in babyhood is babyhood is surdomutismsurdomutism. .

MutismMutism, i.e. inability to speak, can be at , i.e. inability to speak, can be at hysteriahysteria..

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Praxis is skills, acquired during Praxis is skills, acquired during the lifethe life

Apraxia Apraxia is is named to carry out named to carry out different practical domestic and different practical domestic and professional motive skills, produced professional motive skills, produced in the process of life, that appear in in the process of life, that appear in spite of absence of paralysesspite of absence of paralyses, , complete safety of muscles force, complete safety of muscles force, deep sense and mechanisms of deep sense and mechanisms of coordination. coordination.

Next typesNext types of apraxia are of apraxia are distinguished.distinguished.

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Efferent (kinetic), or dynamic, apraxiaEfferent (kinetic), or dynamic, apraxia arises up at the damage of arises up at the damage of motor areas motor areas

of cortexof cortex. It is characterized by violation . It is characterized by violation of of сосоmplex motions, skills. mplex motions, skills.

Disintegration of necessary set of Disintegration of necessary set of motions arises up, a patient can not motions arises up, a patient can not fasten the button, to inflame a match, to fasten the button, to inflame a match, to pour water in glass or patient tries to do pour water in glass or patient tries to do it by a healthy hand. it by a healthy hand.

This form of apraxia arises up more This form of apraxia arises up more frequent at the defeat of left hemispherefrequent at the defeat of left hemisphere

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Structural apraxiaStructural apraxia arising up at the defeat of arising up at the defeat of supramarginal supramarginal

gyrusgyrus, is characterized by violation of , is characterized by violation of those motions, which require safety of those motions, which require safety of spatial orientation. spatial orientation.

Patients become confused in the direction Patients become confused in the direction of motion (go to the left, if it is needed to of motion (go to the left, if it is needed to the right), can not correctly get dressed, the right), can not correctly get dressed, mixing up a right and left sleeve, right mixing up a right and left sleeve, right and left boot, can not make a figure from and left boot, can not make a figure from its elements, become confused in the its elements, become confused in the decision decision of position of part of body.of position of part of body.

For example, we ask to do a square from For example, we ask to do a square from matches…matches…

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Ideatoric apraxiaIdeatoric apraxia arising up at the defeat ofarising up at the defeat of angular angular

gyrusgyrus, is characterized by violation , is characterized by violation of idea of motions, that is correct of idea of motions, that is correct plan of complex motion.plan of complex motion.

For example, we ask to smoke For example, we ask to smoke sigarette…sigarette…

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Gnosis - Gnosis - the ability to the ability to recognizerecognize objects objects byby their their sensory perceptionsensory perception

.... Violation of recognition of Violation of recognition of

irritants, signals acting from an irritants, signals acting from an external environment is named external environment is named agnosiaagnosia. .

There are next kindsThere are next kinds..

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Agnosia of superficial and deep Agnosia of superficial and deep sensationsensation

is observed at the defeat of is observed at the defeat of departments, that are located near departments, that are located near post-central gyrus. post-central gyrus.

The difficult types of sensitiveness The difficult types of sensitiveness are thus violated — sense of are thus violated — sense of localization, discriminations, two- localization, discriminations, two- and three-spatial senses. and three-spatial senses.

AstereognosiaAstereognosia – it’s impossible to – it’s impossible to determine objects by touch. determine objects by touch.

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Violation of chart of bodyViolation of chart of body At the defeat of the right hemisphere of parietal At the defeat of the right hemisphere of parietal

lobe. lobe. There areThere are - - AnosognosiaAnosognosia — no awareness of paralysis of — no awareness of paralysis of

extremities. The paralysis is not noticed. The extremities. The paralysis is not noticed. The patients assure that can move, to move by the patients assure that can move, to move by the paralyzed extremities, but don’t “want” to do it paralyzed extremities, but don’t “want” to do it only. only.

Autotopagnosia Autotopagnosia — no recognition of parts of own — no recognition of parts of own body. Such patients can not find the certain part body. Such patients can not find the certain part of body or show other parts of body. of body or show other parts of body.

PsevdopolymeliaPsevdopolymelia — the feeling of false — the feeling of false extremities. More frequent the patients feel the extremities. More frequent the patients feel the third hand. third hand.

It should be noted that all these original It should be noted that all these original symptoms quite often arise up at patients with a symptoms quite often arise up at patients with a more or less safe psyche, at presence of correct more or less safe psyche, at presence of correct orientation in time, environment.orientation in time, environment.

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Auditory agnosiaAuditory agnosia *Heartfelt deafness**Heartfelt deafness* arises up at the arises up at the

defeat of defeat of temporal lobetemporal lobe. . It consists in the loss of ability to It consists in the loss of ability to

know objects on sounds know objects on sounds characteristic for them (clock — on characteristic for them (clock — on ticking, machine — on the hum of ticking, machine — on the hum of motor. motor.

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The damage of internal surface The damage of internal surface of temporal gyres causesof temporal gyres causes

olfactory and taste agnosiaolfactory and taste agnosia..

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Visual agnosiaVisual agnosia *Heartfelt blindness**Heartfelt blindness* can arise up at can arise up at

the defeat of the defeat of outward surface of outward surface of occipital gyresoccipital gyres. .

Patients Patients throw away the opportunity throw away the opportunity to know and understand visibleto know and understand visible, that , that brings them over to complete brings them over to complete disorientation. disorientation.

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Symptoms of defeat Symptoms of defeat

of separate cortex lobesof separate cortex lobes

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Page 26: Higher cortex function

Agraphia

Broca’s aphasia

central paralyses

on the opposite half of body

Center of turning of head and eyes to the opposite side

Extrapyramidal disorders

Frontal ataxiaMotor apraxia

Grabbing reflexFrontal psyche

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Frontal lobe.Frontal lobe. Defeat of precentral gyrus -Defeat of precentral gyrus - there are there are

central paralyses on the opposite part of central paralyses on the opposite part of body, which carry a monoplegic character, body, which carry a monoplegic character, spreading on a hand or leg depending on spreading on a hand or leg depending on the place of defeat of precentral gyrus. the place of defeat of precentral gyrus.

Defeat of back departments of median Defeat of back departments of median frontal gyrus - frontal gyrus - there is the turn of head there is the turn of head and eyes toward a nidus.and eyes toward a nidus.

Frontal ataxiaFrontal ataxia which shows up, mainly, by which shows up, mainly, by disorders of walking and placed. A patient disorders of walking and placed. A patient cann’t stay in vertical position and fall cann’t stay in vertical position and fall (astasia) and can not walk (abasia). (astasia) and can not walk (abasia).

Agraphia, Broca’s aphasia, motor apraxiaAgraphia, Broca’s aphasia, motor apraxia.. Grabbing reflex, frontal psycheGrabbing reflex, frontal psyche, ,

untidiness, no ended motion. untidiness, no ended motion.

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Frontal lobe.Frontal lobe. Extrapyramidal disorders Extrapyramidal disorders If the defeat is located on the basal If the defeat is located on the basal

surface of frontal lobe –surface of frontal lobe – Anosmia Anosmia (homolateral loss s(homolateral loss smellmell).). AmavrosAmavros (homolateral blindness). (homolateral blindness). Foster-Cennedy’ symptom (in Foster-Cennedy’ symptom (in

tumor)– homolateral atrophy of the tumor)– homolateral atrophy of the visual nerve disk and heterolateral visual nerve disk and heterolateral stagnation of this.stagnation of this.

If there is the defeat of If there is the defeat of corticobulbar tracts in two sides corticobulbar tracts in two sides

Suprabulbar syndromeSuprabulbar syndrome

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Anosmia

Amavros

n. opticus

Page 30: Higher cortex function

Bulbar and Suprabulbar syndromsBulbar and Suprabulbar syndroms1. Bulbar syndrom occurs in the defeat of nuclears 1. Bulbar syndrom occurs in the defeat of nuclears

of IX, X, XII cranial nerves.of IX, X, XII cranial nerves.2. Suprabulbar syndrome occurs in the defeat of 2. Suprabulbar syndrome occurs in the defeat of

corticobulbar tracts in two sides. corticobulbar tracts in two sides. Similar symptomsSimilar symptoms

DysartriaDysartria DysphagiaDysphagia DysphoniaDysphonia

DistinctionsDistinctions 1. – there are loss of pharyngeal (or gag) and 1. – there are loss of pharyngeal (or gag) and uvular (or palatal) reflexesuvular (or palatal) reflexes - - atrophy and fibrillations of tongueatrophy and fibrillations of tongue 2. -2. - there are saving of reflexes, no atrophythere are saving of reflexes, no atrophy - positive symptoms of oral automatism, - positive symptoms of oral automatism,

violent weeping, laughter violent weeping, laughter

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Parietal lobeParietal lobe

Defeat of postcentral gyrus Defeat of postcentral gyrus - t- the loss of he loss of all types of sensation on the opposite all types of sensation on the opposite part of body. In connection with a strict part of body. In connection with a strict somatotopic representative office in the somatotopic representative office in the cortex of postcentral gyrus a sensation cortex of postcentral gyrus a sensation is violated in the proper parts of body. is violated in the proper parts of body.

Agnosia of superficial and deep Agnosia of superficial and deep sensation+asteregnosis.sensation+asteregnosis.

Violation of chart (scheme) of body Violation of chart (scheme) of body (defeat is in the right hemisphere)(defeat is in the right hemisphere)

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Anesthesia on the opposite part of body

Agnosia of superficial

and deep sensation+

asteregnosis

Violation of chart of body (in right hemisphere)

AlexiaAcalculia

Apraxia

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Temporal gyrusTemporal gyrusThe defeat of outward surface of temporal The defeat of outward surface of temporal

lobelobe.. Auditory agnosiaAuditory agnosia Feeling of falling, instability, attacks of Feeling of falling, instability, attacks of

dizzinessdizziness Wernicke's aphasiaWernicke's aphasia

The defeat of medial surface of temporal The defeat of medial surface of temporal gyrusgyrus..

Taste, smell agnosiaTaste, smell agnosiaThe defeat of white matter.The defeat of white matter.

Homonym quadrant hemianopsiaHomonym quadrant hemianopsia (overhead – if the defeat is in low part, (overhead – if the defeat is in low part, lower – if the defeat is in above part of lower – if the defeat is in above part of Graciole bunch) Graciole bunch)

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Auditory agnosia

Wernicke'saphasia

Feeling of falling, instability,

attacks of dizziness

Page 35: Higher cortex function

taste, smell agnosia

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Occipital gyrusOccipital gyrus The defeat of median surface of occipital The defeat of median surface of occipital

gyrusgyrus in area of in area of sulcus calcarinus sulcus calcarinus (calcareous)(calcareous) is accompanied by quadrant is accompanied by quadrant hemianopsia on opposite side. hemianopsia on opposite side.

At the isolated damage of the areas of At the isolated damage of the areas of cortex, located in the overhead (cuneus) cortex, located in the overhead (cuneus) or lower (gyrus linguales (lingual) or lower (gyrus linguales (lingual) department of department of sulcus calcarinussulcus calcarinus, arises , arises up lower or overhead homonym quadrant up lower or overhead homonym quadrant hemianopsia.hemianopsia.

The defeat of outward surface of occipital The defeat of outward surface of occipital gyrusgyrus

Visual agnosiaVisual agnosia

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Lowerhomonym quadrant

hemianopsiaOverhead

homonym quadrant hemianopsia

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Symptoms of irritationsSymptoms of irritations The irritation of precentral gyrusThe irritation of precentral gyrus by a by a

pathological process is accompanied by pathological process is accompanied by the attacks of the attacks of Jackson motor epilepsyJackson motor epilepsy (they are the aura of epileptic attack), (they are the aura of epileptic attack), expressed in the clonic or tonic-clonic expressed in the clonic or tonic-clonic cramps of the limited muscles groups cramps of the limited muscles groups proper to the annoyed area of cortex - proper to the annoyed area of cortex - cramps arise up on side, opposite to the cramps arise up on side, opposite to the pathological nidus in a brain, and are not pathological nidus in a brain, and are not accompanied by the loss of consciousness. accompanied by the loss of consciousness.

The irritation of motor area in medial The irritation of motor area in medial frontal gyrus frontal gyrus results in combination results in combination turn turn of head and eyesof head and eyes aside of the aside of the pathol.pathol. nidus. nidus.

The irritation of opercular part of lower The irritation of opercular part of lower frontal gyrusfrontal gyrus causes the attacks of causes the attacks of rhythmic rhythmic masticatory masticatory motionsmotions, smacking, , smacking, lickinglicking..

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Symptoms of irritationsSymptoms of irritations The irritation by the pathological process of The irritation by the pathological process of

postcentral gyruspostcentral gyrus results in appearance of results in appearance of paresthesia in the areas of body, proper to the paresthesia in the areas of body, proper to the annoyed regions of cortex. They are annoyed regions of cortex. They are Jackson Jackson sensor epilepsy sensor epilepsy (the aura of epileptic attack).(the aura of epileptic attack).

At the irritation of middle part of overhead At the irritation of middle part of overhead temporal gyrustemporal gyrus, where the cortex representation , where the cortex representation of auditory analyzer is located, there are of auditory analyzer is located, there are auditory auditory hallucinationshallucinations (noise, ringing, sing). (noise, ringing, sing).

The irritation of parahyppocamp gyrusThe irritation of parahyppocamp gyrus, especialy , especialy its hook conduces to the origin of its hook conduces to the origin of olfactory, smell olfactory, smell and taste hallucinationsand taste hallucinations..

The irritation of cortex in the The irritation of cortex in the medial surface of medial surface of occipital gyrusoccipital gyrus can result in appearance of can result in appearance of simple simple hallucinationshallucinations (photopsia) in the halves of (photopsia) in the halves of eyeshot opposed to the nidus.eyeshot opposed to the nidus.

The irritation of cortex in theThe irritation of cortex in the outward surface of outward surface of occipital gyrus occipital gyrus can result in appearance of can result in appearance of complex hallucinationscomplex hallucinations (pictures, films). (pictures, films).