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The role of different class neurons of cat visual cortex in the local synchronization
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International Journal of Psychophysiology 94 (2014) 120–261
on a treadmill in the frontoparallel plane. Scrambled motions (SM) were made by randomizing the spatial locations of each point-light of the PLW. BVMs consisted of 128 white dots (0.06° diameter), moving in a direction opposite to the PLW walking direction with one of three velocities according to the PLW walking velocity: quarter, equal, and fourfold. Through a mirror attached to a head coil in an MRI scanner, subjects viewed the screen displaying visual stimuli.Procedure: Six conditions were examined in an event-related fMRI paradigm as 2 (PLW or SM) × 3 BVM velocity. Subjects were asked to press a button according to judgment of the walking directions of both PLWs and SMs. The fMRI time series were obtained using a 1.5 T MRI system. The fMRI data were analyzed using SPM8. Results: 2 (PLW or SM) × 3 (velocity) ANOVAs for fMRI data showed significant interactions in the left anterior superior temporal sulcus (aSTS). Subsequent ANOVA results revealed that a main effect of velocity was significant among conditions with PLW in the left aSTS. Subsequent t-tests revealed that activation under “equal” and “fourfold” conditions with PLW were significantly greater than those under “quarter” conditions with PLW in the left aSTS. Discussion and conclusion: These findings provide evidence for integration of the walking velocity of PLW and velocity of BVM in the aSTS. doi:10.1016/j.ijpsycho.2014.08.807
The role of different class neurons of cat visual cortex in the local synchronization Evgeniya Belova, Irina Ischenko A.B. Kogan Research Institute of Neurocybernetics, Southern Federal University, Russia Synchronized neuronal activity is considered to be related to a mechanism for visual feature binding. The role of different class neurons in the synchronization is not fully understood. The goal of the present study was to investigate the local synchronized neuronal activity and the role of different class neurons in neural synchrony. The neurons of cat visual cortex (149 cells) were recorded extracellularly in response to visual stimuli. Sinusoid gratings were used for visual stimulation. The neurons were classified based on a wide variety of electrophysiological properties and compared with well-known functional classes of neurons: Fast Spiking (FS), Fast Repetitive Bursting (FRB), Regular Spiking (RS), Intrinsically Bursting (IB). We estimated the strength of the synchronization between the pairs of neurons using crosscorrelation methods. Thirteen pairs of neurons that were strongly or at least moderately synchronized had a shifted peak in the crosscorrelogram of 2–10 ms. The neurons with short-duration of the spike and unimodal distributions of interspike interval histograms with spikes at modal frequencies of 300–500 Hz were classified as FS cells (17 cells). FRB neurons (36 cells) with narrow spikes and bimodal distributions of interspike intervals generated bursts of spikes with intraburst frequencies of 330–500 Hz. The wide-spike cells with RS type of activity were characterized by unimodal distributions of interspike intervals with an average modal frequency of 88.5 Hz (64 cells). Neurons with wide spikes and bimodal interspike intervals were classified as IB neurons (32 cells). We measured orientation tuning with respect to firing rate and selected 57 pairs of cells with similar preferred orientations. It was revealed that activity of these neurons was strongly or moderately synchronized in response to preferred orientations. The neurons with short spike and FRB type of activity were the first that were engaged in the synchronization. The cells with wide spike and RS or IB type of activity followed the FRB and FS neurons. The results of the investigation give the evidence that FRB neurons initiate the process of
forming the pattern of synchronous neural activity of functional groups or cell assemblies to process incoming sensory information. doi:10.1016/j.ijpsycho.2014.08.808
Specific “vision deficit”: Description and primary analysis Gennady S. Voronkov The Ì.V. Lomonosov Moscow State University, Russia Background: The phenomenon, referred here as specific “vision deficit” (SVD), is broadly known in ophthalmology. However, the generally accepted description and explanation of its nature are absent. SVD has been detected in all “patients”, including those with normal vision. It becomes evident upon a strong narrowing of the monocularly visible field by means of the ophthalmic set diaphragm. SVD appears as a translucent web-like patch which covers much of the visible field and prevents to clearly see the letters of the ophthalmic table. SVD properties: (1) In SVD patch, two pictures appeared simultaneously, stable and unsteady. (2) The stable picture defines a general patch form and can contain stable inclusions as whitish “vesicles”; the patch form remains unchanged after winking and the vesicles save their specific location for the given eye, constant through the research sessions. (3) The unsteady picture is the various-size-andform dark and whitish inclusions, appearing after winking, come downwards or remain but disappear after the following winking. (4) The SVD patch and its all stable and dynamic inclusions do not shift with a gaze relative to the background objects visible through the diaphragm. (5) But they are displaced in the background along with the diaphragm displacement when the gaze is fixed at some object of the background. (6) They do not turn round together with diaphragm at its rotation. (7) But they (and their movement direction) turn round together with inclination of the head to the side. (8) The SVD patch is seen simultaneously in all diaphragms if several of them are located not far from one another. Herewith each SVD patch is similar to those created by the rest diaphragms. (9) There is an observation that SVD patch is more expressed in the eye with a greater vision deficit. Analysis: Properties 3 and 7 are not consistent with the exclusively holographic hypothesis of SVD patch origin. Property 4 is not consistent with the hypothesis about SVD patch inclusions as manifestations of inclusions and defects on the cornea, lens, vitreous or on retina. The SVD properties suggest the complex SVD patch nature. We discuss the possibility to create a partial SVD picture on retina by light reflected from mirror elements which are supposedly identified as such between the receptor and vascular layers. We introduce the notions “stabilized retina image”, “constant screen” and “competitive relations” between the retinotopic projections creating the vision sensations.
doi:10.1016/j.ijpsycho.2014.08.809
Psychophysiological analysis of multidimensional structure of brightness perception in normal and altered states of consciousness Andrey A. Kiselnikov, Ivan S. Pozdniakov, Anastasiya O. Myasnichenko, Alexander V. Vartanov, Janna M. Glozman, Stanislav A. Kozlovskiy, Maria M. Pyasik Lomonosov Moscow State University, Russia Background: Application of multidimensional scaling to studying color and brightness perception has solid history but complex brain-
International Journal of Psychophysiology 94 (2014) 120–261
on a treadmill in the frontoparallel plane. Scrambled motions (SM) were made by randomizing the spatial locations of each point-light of the PLW. BVMs consisted of 128 white dots (0.06° diameter), moving in a direction opposite to the PLW walking direction with one of three velocities according to the PLW walking velocity: quarter, equal, and fourfold. Through a mirror attached to a head coil in an MRI scanner, subjects viewed the screen displaying visual stimuli.Procedure: Six conditions were examined in an event-related fMRI paradigm as 2 (PLW or SM) × 3 BVM velocity. Subjects were asked to press a button according to judgment of the walking directions of both PLWs and SMs. The fMRI time series were obtained using a 1.5 T MRI system. The fMRI data were analyzed using SPM8. Results: 2 (PLW or SM) × 3 (velocity) ANOVAs for fMRI data showed significant interactions in the left anterior superior temporal sulcus (aSTS). Subsequent ANOVA results revealed that a main effect of velocity was significant among conditions with PLW in the left aSTS. Subsequent t-tests revealed that activation under “equal” and “fourfold” conditions with PLW were significantly greater than those under “quarter” conditions with PLW in the left aSTS. Discussion and conclusion: These findings provide evidence for integration of the walking velocity of PLW and velocity of BVM in the aSTS. doi:10.1016/j.ijpsycho.2014.08.807
The role of different class neurons of cat visual cortex in the local synchronization Evgeniya Belova, Irina Ischenko A.B. Kogan Research Institute of Neurocybernetics, Southern Federal University, Russia Synchronized neuronal activity is considered to be related to a mechanism for visual feature binding. The role of different class neurons in the synchronization is not fully understood. The goal of the present study was to investigate the local synchronized neuronal activity and the role of different class neurons in neural synchrony. The neurons of cat visual cortex (149 cells) were recorded extracellularly in response to visual stimuli. Sinusoid gratings were used for visual stimulation. The neurons were classified based on a wide variety of electrophysiological properties and compared with well-known functional classes of neurons: Fast Spiking (FS), Fast Repetitive Bursting (FRB), Regular Spiking (RS), Intrinsically Bursting (IB). We estimated the strength of the synchronization between the pairs of neurons using crosscorrelation methods. Thirteen pairs of neurons that were strongly or at least moderately synchronized had a shifted peak in the crosscorrelogram of 2–10 ms. The neurons with short-duration of the spike and unimodal distributions of interspike interval histograms with spikes at modal frequencies of 300–500 Hz were classified as FS cells (17 cells). FRB neurons (36 cells) with narrow spikes and bimodal distributions of interspike intervals generated bursts of spikes with intraburst frequencies of 330–500 Hz. The wide-spike cells with RS type of activity were characterized by unimodal distributions of interspike intervals with an average modal frequency of 88.5 Hz (64 cells). Neurons with wide spikes and bimodal interspike intervals were classified as IB neurons (32 cells). We measured orientation tuning with respect to firing rate and selected 57 pairs of cells with similar preferred orientations. It was revealed that activity of these neurons was strongly or moderately synchronized in response to preferred orientations. The neurons with short spike and FRB type of activity were the first that were engaged in the synchronization. The cells with wide spike and RS or IB type of activity followed the FRB and FS neurons. The results of the investigation give the evidence that FRB neurons initiate the process of
forming the pattern of synchronous neural activity of functional groups or cell assemblies to process incoming sensory information. doi:10.1016/j.ijpsycho.2014.08.808
Specific “vision deficit”: Description and primary analysis Gennady S. Voronkov The Ì.V. Lomonosov Moscow State University, Russia Background: The phenomenon, referred here as specific “vision deficit” (SVD), is broadly known in ophthalmology. However, the generally accepted description and explanation of its nature are absent. SVD has been detected in all “patients”, including those with normal vision. It becomes evident upon a strong narrowing of the monocularly visible field by means of the ophthalmic set diaphragm. SVD appears as a translucent web-like patch which covers much of the visible field and prevents to clearly see the letters of the ophthalmic table. SVD properties: (1) In SVD patch, two pictures appeared simultaneously, stable and unsteady. (2) The stable picture defines a general patch form and can contain stable inclusions as whitish “vesicles”; the patch form remains unchanged after winking and the vesicles save their specific location for the given eye, constant through the research sessions. (3) The unsteady picture is the various-size-andform dark and whitish inclusions, appearing after winking, come downwards or remain but disappear after the following winking. (4) The SVD patch and its all stable and dynamic inclusions do not shift with a gaze relative to the background objects visible through the diaphragm. (5) But they are displaced in the background along with the diaphragm displacement when the gaze is fixed at some object of the background. (6) They do not turn round together with diaphragm at its rotation. (7) But they (and their movement direction) turn round together with inclination of the head to the side. (8) The SVD patch is seen simultaneously in all diaphragms if several of them are located not far from one another. Herewith each SVD patch is similar to those created by the rest diaphragms. (9) There is an observation that SVD patch is more expressed in the eye with a greater vision deficit. Analysis: Properties 3 and 7 are not consistent with the exclusively holographic hypothesis of SVD patch origin. Property 4 is not consistent with the hypothesis about SVD patch inclusions as manifestations of inclusions and defects on the cornea, lens, vitreous or on retina. The SVD properties suggest the complex SVD patch nature. We discuss the possibility to create a partial SVD picture on retina by light reflected from mirror elements which are supposedly identified as such between the receptor and vascular layers. We introduce the notions “stabilized retina image”, “constant screen” and “competitive relations” between the retinotopic projections creating the vision sensations.
doi:10.1016/j.ijpsycho.2014.08.809
Psychophysiological analysis of multidimensional structure of brightness perception in normal and altered states of consciousness Andrey A. Kiselnikov, Ivan S. Pozdniakov, Anastasiya O. Myasnichenko, Alexander V. Vartanov, Janna M. Glozman, Stanislav A. Kozlovskiy, Maria M. Pyasik Lomonosov Moscow State University, Russia Background: Application of multidimensional scaling to studying color and brightness perception has solid history but complex brain-