A mediális prefrontális kéreg szerepe az auditoros szenzoros-motoros kapuzó mechanizmusban

Abstract

The limited information processing capacity of the central nervous system makes it necessary to prevent the entry of irrelevant stimuli into the higher neurological centres. To achieve this, a number of mechanisms have been developed that effectively select the volume of incoming information separately and jointly. Sensory-motor-gate mechanisms are the core components of the brain's signal-processing mechanism, which are necessary to select the stimuli that are important to the individual. The filtered information will lead to the development of the organised behavioural process (Graham et al., 1975) (Blumenthal et al., 1996) (Swerdlow et al., 2000) (Fendt et al., 2001). With regard to the experimental examination of this process, perhaps with the greatest relevance, the startle reaction and its modified version, prepulsive inhibition (PPI) plays an essential role. In terms of modality, any strong sensory stimulus can generate a startle response. (In human studies, the form of the acoustic, the use of a tactile-stimulus (air-puff), is a predilection.) The most researched and best-performing form is the reaction induced by an acoustic stimulus. The acoustic startle reflex and its modified version of Prepulsive inhibition show deviations in a number of neuropsychiatric conditions [schizophrenia, schizotype personality disorder, Huntigton's disease, Obsessive compulsive Disorder, OCD, Tourette syndrome, Attention deficit syndrome (FDD, Attention deficit disorder, ADD)] (Swerdlow and Geyer, 1998). The common denominator of the aforementioned diseases is that the decrease in the filtration of incoming sensory information will result in a change in the given motor, along with the cognitive response. A number of metodikes have been developed to test the sensory-motor capation deficit. However, on the basis of the literature review, it is believed that the most accurate results for the examination of the neurological lesions of the absence of inhibition can be served by prepulsive inhibition (PPI). The malfunction of the gating mechanism can contribute to sensory overcharge or flooding, which ultimately leads to cognitive fragmentation, thought, perception disorder and other psychotic symptoms (Braff and Geyer, 1990); (Geyer et al., 1990); (Braff et al., 2001a). The startle reaction is an extremely fast, reflex reaction, suggesting that the relationship between only a few nerve cells creates a distinctive response. However, in addition to the simple primary structure, it is also necessary to observe the approach of stacking mechanisms when designing the appropriate reaction. For example, attention, learning and other cognitive processes, of which the prefrontal cortex is crucial. Prepulsive inhibition is an extremely complex process in itself, which also plays a role in cortical areas, primarily the prefrontal cortex, which performs important regulatory functions in the process. This is indicated by experiments leading to a PPI change following the lesion of the area (Koch and Bubser, 1994); (Japha and Koch, 1999); (Schwabe et al., 2004, Schwabe and Koch, 2004). The extremely complex structure and resultant role of the prefrontal cortex, as well as the very rapid head movement during the startle reaction, which causes a significant movement artefact during registration, is a major obstacle to Electrophysiologic Methods to monitor the operation, the modification and the modified version of the nerve cells in this area, below PPI. In carrying out our tests, we sought to register and analyse neuronal changes in this area.