The cerebrum is divided by the longitudinal fissure in 2 hemispheres, each comprises 5 separate lobes: Frontal Temporal Parietal occipital Insulation frontal, temporal, parietal and occipital lobes cover the surface of the brain; the island cortex is hidden under the Sylvian groove (brain areas.). Although each lobe are associated with specific functions, most activities require the coordination of many areas of both hemispheres. Thus, for processing. B. on both sides of complex visual stimuli, although the occipital lobe of the visual processing is also essential parts of the parietal, temporal and frontal lobe. Brain areas. The function is largely lateralized. The visual, tactile and motor activity of the left side of the body is mainly controlled by the right hemisphere, and vice versa. In certain complex functions both hemispheres are involved, however, they are predominantly of a hemisphere dominated (cerebral dominance). So z. B. the left hemisphere typically dominant for the language and the right for the spatial perception. The cerebral cortex contains primary sensory area The primary engine compartment Several association areas, including heteromodaler association areas, the primary sensory areas directly receive bodily sensations, auditory, visual, olfactory and gustatory stimuli from the specialized sense organs and of peripheral receptors. In the association areas, which are provided to one or more sensory perceptions regarding which sensory stimuli are processed further. The primary motor cortex generated arbitrary movements of the body; the motor association areas help plan and execute complex motor activity. “Heteromodal association areas” are not limited to a single motor or sensory functions, but get convergent information from different sensory and motor areas of the brain. Heteromodal association areas in the frontal, temporal and parietal lobes integrate sensory input, the motor feedback and other information with instinctive and acquired memory contents. This integration allows learning and the generation of thought, expression and behavior. Frontal lobe The frontal lobes are the central sulcus. They are crucial for the planning and execution of a learned and goal-directed behavior; in them also many inhibitory functions are localized. There are several functionally distinct regions in the frontal lobes: The primary motor cortex forms the rear portion of the precentral gyrus. The primary motor cortex on one side controls all movements on the contralateral side of the body (shown in a spatial representation, the Homunkulus- homunculus.); 90% of motor fibers each hemisphere cross the midline in the brainstem. Thus, damage to the motor cortex in one hemisphere weakness or paralysis effect mainly on the contralateral side of the body. The mid frontal cortex (also called medial prefrontal area) is important for arousal and motivation. For large lesions in this area, which extends into the front cortex area (frontal pole) expand, patients are sometimes abulisch (apathetic, inattentive and clear in their reaction slows). The orbitofrontal cortex (also orbital prefrontal area genannt- brain areas.) Is involved in modulating social behavior. Patients with orbitofrontal lesions can become emotionally labile, indifferent to the consequences of their actions, or both. You can be alternately euphoric, funny, vulgar and indifferent to social nuances. A both acute trauma in this area can make patient talkative, restless and without distance. The disinhibition and abnormal behaviors that may develop with aging and in many types of dementia, stir likely from a frontal lobe degeneration, particularly the Orbitofrontalkortex, ago. The left posteroinferiore frontal cortex (also Broca’s area or posteroinferiores prefrontal area genannt- areas of the brain.) Controls the speech production. Lesions in this area cause expressive aphasia (impaired word utterance). (Also called dorsolaterales prefrontal area) of the dorsolateral frontal cortex processed just acquired information-a function that is called working memory. Lesions in this area can the capacity for information storage and processing in real time affect (eg. As Rückwärtsbuchstabieren of words or change in sequence between letters and numbers). Homunculus. Certain parts of the cortex control specific motor and sensory functions on the contralateral side of the body. The extent of cortical representation of a body part varies, z. B. is the cortex region, which controls the hand, larger than the area that controls the shoulder. The “map” of these body parts is called homunculus ( “little man”). Several parietal areas in the parietal lobes have specific functions. The primary somatosensory cortex in postrolandischen area (postcentral gyrus) of the front parietal integrated somästhetische stimuli for the detection of shape, structure and weight of articles. The primary somatosensory cortex on one side receives the complete somatosensory input from the contralateral side of the body (homunculus.). Lesions of the anterior parietal lobe can cause difficulties in the detection of objects by touch (astereognosis). Areas which are posterolateral from postcentral gyrus, producing spatially-visual links and integrate these observations with other sensations, and so lead to the recognition of the path of movement of a moving object. These areas also mediate proprioception (position perception of the body in space). Parts of the central parietal lobe of the dominant hemisphere are involved in skills such as arithmetic, writing, left-right orientation and finger perception. Lesions in the angular gyrus can cause (Gerstmann syndrome) deficits in writing, arithmetic, the left-right orientation and Fing heritage Nennens. The nondominant parietal lobe integrates the contralateral side of the body into its surroundings, allowing the perception of space and is important for skills such as drawing. An acute injury to the nondominant parietal lobe may cause neglect of the contralateral side (usually the left), resulting in a failure to recognize this side of the body, the environment and any violation of this page results (anosognosia). Patients with a large lesion can rechtsparietalen z. B. negate the existence of a left-Plegie. Patients with smaller lesions can the ability to perform learned motor skills lose (z. B. tightening, other well-learned activities) -a spatial-manual deficit called apraxia. Temporal The temporal lobes are responsible for auditory perception, language comprehension, visual memory, declarative (factual) memory and emotional processing. Patients with right-sided Temporallappenläsionen usually lose the ability to interpret nonverbal auditory stimuli (eg. As music). In lesions of the left temporal lobe, there is significant disruption of recognition, memory and language education. Patients with epileptogenic foci in the medial temporal lobe limbic part of the often have complex partial seizures, characterized by with uncontrollable emotions and autonomic, cognitive or emotional disorders. Occasionally, personality changes are observed in such patients, which are characterized by lack of humor, philosophical principle religion and compulsion. Patients may olfactory hallucinations and hypergraphia (to write an overwhelming urge) have. Occipital lobe: The occipital lobes contain the primary visual cortex visual association areas lesions of the primary visual cortex leading to a form of central blindness, called Anton syndrome; the patients are unable to detect objects by observing and taking not true at this deficit, often confabulate descriptions of what they see. Seizures, including the occipital lobe can cause visual hallucinations, often consist of colored lines or nets that are localized in the contralateral visual field. Insula The insula processed sensory and autonomic information from the viscera area. It plays a role in certain language functions, as demonstrated by the aphasia in patients with lesions in the island area. The insula processes aspects of pain and temperature sensation and possibly taste perception. Pathophysiology Cerebral disorder may be focal or global. Focal and global processes may also affect subcortical systems and vigilance change (eg. As stupor or coma cause) or the mental integration change (eg. As cause delirium). A focal disorder resulting mostly from structural changes (eg., Tumors, stroke, trauma, malformations, gliosis, demyelination). The manifestations depend on the location of the lesion, from their size and speed of development. Lesions that have a diameter <2 cm or develop slowly, may be asymptomatic. Larger lesions, rapidly developing lesions (rather than weeks or months as many years) and lesions that affect both hemispheres simultaneously be symptomatic more likely. Focal lesions of the white matter can the connecting webs break between brain areas and a Diskonnektionssyndrom cause (inability to perform an action that requires the coordinated activity of ? 2 brain regions, even though the basic functions of each region are obtained). Global losses caused by toxic-metabolic disorders or sometimes by diffuse inflammation, vasculopathy, major trauma or disseminated cancers; these disorders affect many areas of the cerebral function. Regeneration Recovery from brain injury depends in part on the following properties of the brain from: Platizität the remaining cerebrum redundancy The plasticity (ability of a region of the brain to change its function) of the cerebrum varies individually and is influenced by the age and general health. Plasticity is most pronounced in the developing brain. Thus, can. As in the dominant hemisphere before age 8, the other half of the brain play a near-normal language function in severe damage to the language areas. The capacity to recover from brain injuries after the first decade of life is substantial, but severe damage more often leads to permanent deficits. A comprehensive reorganization of brain function after injury is uncommon in adults, although the plasticity in certain specific areas of the brain persists for life. Redundancy refers to involve the ability of more than one area of ??the brain, the same function auszuführen.Zerebrale fault syndromes to the specific syndromes include agnosia amnesia (including transient global amnesia) aphasia apraxia psychiatric disorders (eg., Depression, psychosis, anxiety disorders) sometimes similar elements. Dysarthria, a neuromotor disorder can cause symptoms similar to those of aphasia. Diagnosis Clinical examination often neuropsychological tests In general, the diagnosis of cerebral dysfunction occurs clinically, often supported by neuropsychological tests. The clarification of the cause normally requires laboratory tests (blood and cerebrospinal fluid sometimes) and imaging of the brain, either structurally (CT, MRI) or functionally (PET, SPECT).


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