Fields Brodmann - sections of the cerebral cortex, differing in their cytoarchitectonics (structure at the cellular level). There are 52 Brodmann cytoarchitectonic fields.
Field table according to Brodman, their localization, functions and violations
Located in the postcentral gyrus, a site of the parietal lobe
The somatosensory area, the primary zone, combined as an SI area, ends with superficial and deep sensory pathways
In case of damage, anesthesia or hypesthesia of all types of sensitivity occurs in the corresponding (depending on the location of the lesion) parts of the body from the opposite side. With irritation, paresthesias occur in the areas of the body corresponding to the irritated areas of the cortex. Such paresthesias (sensitive Jacksonian seizures) can be the aura of a generalized epileptic seizure.
Motor area. Located within the precentral gyrus
The pyramidal path begins, which ends on the motor neurons of the spinal cord and the motor nuclei of the cranial nerves, which provides conscious movements. The neurons that innervate the pharynx and larynx are located in the lower part of the precentral gyrus. Next, in ascending order, are the neurons that innervate the face, arm, trunk, and leg. Thus, all parts of the human body are projected in the precentral gyrus, as it were, upside down. This pattern was noted by the Canadian neurosurgeon Penfield, and the image he received is called the "motor homunculus".
Motoneurons of the 4th field control the voluntary movements of the skeletal muscles of the opposite half of the body, since most of the pyramidal fibers go to the opposite side in the lower part of the medulla oblongata
When the precentral gyrus is damaged, central paresis or paralysis occurs on the opposite side of the body in a monotype (paresis or paralysis occurs either in the arm or in the leg or facial muscles, depending on the location of the lesion). When the precentral gyrus is irritated, attacks of Jacksonian epilepsy occur, which are characterized by clonic twitching of individual muscle groups corresponding to the irritated areas of the cortex. Jacksonian seizures can develop into a general convulsive seizure.
Located in the superior parietal lobe behind the postcentral gyrus
The secondary somat receives information mainly from the primary somatosensory zone-sensory zone S2, analysis and detailed processing of information, both about deep and superficial sensitivity, takes place. These fields provide stereognosis - recognition of objects by touch.
Astereognosis is a violation of the ability to recognize an object by touch. A person clearly defines the properties of an object: "hard" or "soft", "cold" or "warm", "smooth" or "embossed" and more. At the same time, he loses the ability to analyze the information received and determine what kind of object it is.
Located in the anterior sections of the precentral and posterior sections of the superior and middle frontal gyri.
The premotor cortex and the additional motor cortex (secondary motor zone), in which the plan and sequence of movements are formed, send efferent impulses to the cerebellum and the basal ganglia of the extrapyramidal system.
The emergence of kinetic (synonymous with efferent, kinetic, premotor, dynamic) apraxia. It is characterized by a violation of complex movements (for example, connecting several points on paper with lines). With this form of apraxia, motor perseverations (repetitions), slowness of movements, and general muscle tension are observed.
Located in the upper parietal lobe between the postcentral gyrus and the occipital lobe
Receives information from the primary somatosensory zone, as well as from the visual cortex of the occipital lobes. It is a tertiary projection field (an associative zone in the place where various analyzers overlap, in which various signals are integrated, the corresponding sensations are formed, complex analytic-synthetic functions are performed), the information received in the postcentral gyrus is analyzed and processed both about deep and superficial sensitivity. These fields provide stereognosis - recognition of objects by touch.
Astereognosis, which is described in "Field 5".
Also, when the cytoarchitectonic field of Brodmann 7 is damaged in the area of the right (non-dominant) hemisphere, autopoagnosia occurs - a violation of the recognition of one's own body and its parts. A patient with a violation of the body scheme may seem that his limbs are either enlarged (macropsia) or reduced (micropsia) in size, or changed not only in size, but also in shape (metamorphopsia). One of the options for auto-diagnosis is agnosia of the fingers. Patients may confuse the right and left sides, claim that they have many arms or legs (polymelia). The same group of disorders can include anosognosia (Anton's syndrome), when the patient is not aware of the presence of a defect (motor, auditory and others) or disease. Anosognosia is often combined with autotopoagnosia and occurs against the background of gross violations of proprioceptive sensitivity
Located in the posterior superior and middle frontal gyri, in front of the premotor zone
The center of the arbitrary eye rotation is located.
Its destruction, damage or defeat causes paralysis of the gaze in the direction opposite to the focus. The patient "looks at the lesion." Usually this symptom is unstable and appears with acute processes in the frontal lobe. When this area is irritated, convulsive twitching of the eyes and head occurs in the direction opposite to the affected hemisphere. These seizures are referred to as cortical, or Jacksonian, epilepsy.
Field 9 dorsolateral prefrontal cortex
Field 10 anterior prefrontal cortex
Field 11 olfactory region
1. Violation of initiative and independence in actions, suppression of speech and motor activity (apathetic-akinetic-abulic state), decreased daily activity, slowing down of interpersonal social reactions.
2. Changes in personality, which is expressed in the appearance of carelessness. Sometimes this takes the form of childishness, inappropriate jokes and puns, meaningless drives, lability, and the surface of emotion or irritability. The ability to worry, worry, and sadness decreases.
3. Some decrease in intelligence, which is usually characterized by loss of composure, instability of attention, inability to perform planned actions. Difficulties arise in the transition from one type of activity to another, perseveration. Goldstein downplays the difficulty of losing the ability to think abstractly, but the authors of this chapter believe that the tendency to think concretely is a manifestation of abulia and perseveration. According to Luria, who considered the frontal lobe as a regulatory mechanism of the body's activity, planned activity is not enough to exercise control and focus on the task. With lesions of the left frontal lobe, intelligence suffers to a greater extent (10 points on the IQ scale) than with damage to the right lobe, probably due to a decrease in verbal skills. In addition, memory is somewhat impaired, possibly due to impairment of the mental ability necessary for memorization and reproduction.
four.Movement disorders such as change in gait and difficulty standing upright, gait with legs wide apart, stooped posture and shallow mincing gait, reaching maximum severity in the inability to stand (Bruns frontal ataxia or gait apraxia) in combination with abnormal postures, and sucking reflexes, disorders of the functions of the pelvic organs.
The insular area, occupying the islet, in its very small lower section is occupied by the interstitial crust separating the new crust from the old one. Basically, it is represented by the fields of the new crust.
associated with the function of speech, in part - with the analysis of olfactory and gustatory sensations
visual area, primary area
analysis of the physical parameters of the stimulus The retina is projected "point to point" according to the retinotopic principle. recognition of simple patterns.
When field 17 is destroyed, loss of visual sensations (cortical blindness) occurs. Different parts of the retina are unequally projected in the 17th Brodmann field and have different locations. With the point destruction of the 17 field, the completeness of the visual perception of the environment is disturbed, since a portion of the field of view falls out. 1. With the destruction of nervous tissue - central scotomas.
2. With the destruction of the entire zone in one of the hemispheres - central homonymous hemianopsia.
3. With the destruction of both zones in two hemispheres - central blindness.
visual area, secondary area
located in the occipital lobe
the nuclear zone of the visual analyzer - the center of perception of written speech, the secondary zone
With the defeat of the 18th Brodmann field, the functions associated with the recognition of the visual image suffer, the perception of writing is impaired.
visual area, tertiary cortex
located in the occipital lobe
nuclear zone of the visual analyzer, secondary zone
various visual hallucinations arise, visual memory and other visual functions suffer.
alexia - loss of the ability to read, understand written signs, as well as paragraph (identical to paraphasia of a violation of written speech) and paralexia (identical to paraphasia of a violation of speech when reading).
Located in the region of the lower parts of the outer surfaces of the temporal lobes
vestibular analyzer center
Field 22 (Acoustic-Gnostic Sensory Speech Center (Wernicke)
Occupies the posterior third of the superior temporal gyrus and part of the inferior parietal lobule. Geshl's curvature
Sensory center of speech. Its main function is to convert auditory signals into neural word codes that activate the corresponding images or concepts, signals caused by speech are sent from the primary auditory cortex.
Damage to this area affects a person's ability to perceive speech sounds as linguistically significant (see Table: Sensory Aphasia (Acoustic-Gnostic Aphasia)). It is associated with the perception of oral speech. With his defeat, sensory aphasia occurs - a person does not understand oral speech (both someone else's and his own). Due to a lack of understanding of his own speech production, the patient's speech takes on the character of a "verbal salad", that is, a set of unrelated words and sounds.
With a joint defeat of the Broca and Wernicke centers (for example, with a stroke, since they are both located in the same vascular basin), total (sensory and motor) aphasia develops,
With the destruction of 22 fields, auditory hallucinations, impaired auditory orientational reactions, musical deafness (Amusia) occur.
cortex of the mediobasal surface of the temporal lobe (pear-shaped and parahippocampal gyrus, hook)
projection fields and the associative zone of the olfactory system
Parosmia and dysosmia - perversions of the perception of olfactory sensations
Olfactory hallucinations are the most complex type of pathology in which there is an imaginary perception of unpleasant odors.
The receptive area of emotional experiences
Transcortical motor aphasia is characterized by a mismatch between spontaneous speech and repetition. Spontaneous speech is grossly impaired, fluency of speech suffers, speech is intermittent. In contrast, the ability to repeat expressions and read aloud are retained. Comprehension of speech is not impaired. Naming items can be a little difficult.
Loss of speech, aphonia
Acoustic-Gnostic Sensory Speech Center (Wernicke)
Located in the region of the posterior parts of the superior temporal gyrus on the left
associated with the ability to memorize words, repetition of words and phrases in grammatical order. This field controls labor processes with speech, is responsible for understanding speech
Amnestic aphasia, acoustic-gnostic aphasia, Semantic aphasia
Angular gyrus, part of Wernicke's zone
Center for the Visual Analyzer of Written Speech, Center for Superficial and Deep Sensitivity, Center for Praxis
Semantic aphasia, manifested by the difficulty of understanding any phrases that are somewhat complex in construction, comparisons, reflexive and attributive logical-grammatical turns, expressing spatial relations. Alexia
Marginal gyrus, part of Wernicke's zone
motor analyzer of complex professional, labor and everyday skills, Center for superficial and deep sensitivity, center for praxis
Afferent kinesthetic motor aphasia, semantic aphasia, amnestic aphasia, apraxia
Located in the region of the middle part of the superior temporal gyrus (Geshla)
nuclear zone of the sound analyzer, primary zone
cortical deafness. Sensory aphasia
Occupies the dorsolateral parts of the temporal lobe
nuclear zone of the sound analyzer, secondary zone. Acoustic-Gnostic Sensory Speech Center (Wernicke)
Sensory aphasia, auditory verbal agnosia,
which is an important component of Wernicke's aphasia
Inferior part of the posterior central gyrus
Field 44 - Broca Center
Located in the posterior region of the inferior frontal gyrus
motor organization of speech is provided and is mainly associated with phonological and syntactic codifications. It is a kinetic-motor verbal analyzer, which processes primarily proprioceptive information.
Broca's aphasia (anarthric syndrome), which is characterized by the impossibility of combining individual speech movements into a single speech act.
Located in front of the motor speech center
Triangular part of Brodmann's field (musical motor center)
Efferent motor aphasia (Broca's aphasia), Motor (vocal) amusia - impairment of the ability to reproduce musical works, if their perception is preserved
posterior prefrontal cortex
Motor analyzer of combined rotation of the head and eyes in different directions
Dynamic aphasia is a violation of productive, active speech, the inability to actively speak
Deviation of the eyes and head to the side and mimicry of attention
Located in the region of the middle part of the superior temporal gyrus
Hearing Analyzer Center
Heschl convolutional syndrome is characterized by the presence of auditory hallucinations. Auditory agnosia is a lack of recognition, a lack of recognition of sounds in the presence of their sensation.