Comparative analysis of the Russian physiological and psychological approaches as a historical foundation for modern experimental studies of inter-analyzer interaction / Análisis comparativo de los enfoques fisiológicos y psicológicos rusos como base histórica para estudios experimentales modernos de interacción inter-analizador

A comparative analysis of the physiological and psychological approaches to the study of inter-analyzer interaction has been carried out in the given article. Their general view on the biological meaning of inter-sensory relationships is underlined, as well as the difference between their indicators to assess the state of intermodal relationships. It is emphasized that the importance of the interaction of analyzer systems is usually stressed in psychological work, yet, the concept of inter-analyzer interaction is not usually operationalized. The authors propose a working definition of the inter-analyzer interaction and justify the adequacy of using Uznadze's methodology for forming a fixed set as a tool for assessing the state of inter-sensory links

Un análisis comparativo de los enfoques fisiológicos y psicológicos para el estudio de la interacción Inter-analizador se ha llevado a cabo en el artículo. Se destaca su visión general sobre el significado biológico de las relaciones intersensoriales, así como la diferencia entre sus indicadores para evaluar el estado de las relaciones intermodales. Se hace hincapié en que la importancia de la interacción de los sistemas de análisis se suele destacar en el trabajo psicológico, sin embargo, el concepto de interacción Inter-analizador no suele ser operativo. Los autores proponen una definición de trabajo del interacción Inter-analizador y justifican la conveniencia de utilizar la metodología de Uznadze para formar un conjunto fijo como herramienta para evaluar el estado de los enlaces Intersensoriales

[Structural retinal and optic nerve changes in patients with post-geniculate visual pathway damage]. / Strukturnye izmeneniia setchatki i zritel'nogo nerva pri porazhenii tsentral'nogo nevrona zritel'nogo puti.

AIM: To establish the possibility of retrograde trans-synaptic neural degeneration following acquired post-geniculate visual pathway damage. MATERIAL AND METHODS: Twenty-two patients with homonymous hemianopia caused by acquired post-geniculate visual pathway damage were examined. Peripapillary retinal nerve fiber layer (RNFL) thickness and ganglion cell complex (GCC) measurements were assessed with RTVue-100 Fourier-domain optical coherence tomography (OCT). RESULTS: In 12 out of 22 patients we detected binocular GCC thinning that was ipsilateral to post-geniculate involvement. Nine patients showed a decrease in the RNFL thickness. However, topographic correspondence between the post-geniculate lesion and RNFL thickness was established for 2 of them only. GCC thinning was more common in patients with hemianopsia acquired more than 6 months ago (p<0.0009). CONCLUSION: Having assessed the ganglion cell complex and retinal nerve fiber layer with OCT, we have proved possible that trans-synaptic retrograde degeneration develops in patients with post-geniculate visual pathway damage.

[Ototoxicity of cisplatin].

The objective of this publication is to summarize "classical" and modern concepts of pathogenesis, clinical features of cisplatin ototoxicity, its screening, and prophylaxis. It is argued that pathogenesis of a cisplatin-induced injury to the inner ear shares common features with the ototoxic mechanisms of action of other pharmaceuticals even though it is characterized by certain important differences. The authors consider the mechanisms of ototropicity, specific cytochemical aspects of cisplatin cytotoxicity that aggravate risk factors, and genetic predisposition to the development of iatrogenic problems. The data are presented on monitoring and experimental aspects of otoprotection for the prevention of cisplatin-induced damage to the auditory analyzer.

Locomotor body scheme.

The concept of body schema has been introduced and widely discussed in the literature to explain various clinical observations and distortions in the body and space representation. Here we address the role of body schema related information in multi-joint limb motion. The processing of proprioceptive information may differ significantly in static and dynamic conditions since in the latter case the control system may employ specific dynamic rules and constraints. Accordingly, the perception of movement, e.g., estimation of step length and walking distance, may rely on a priori knowledge about intrinsic dynamics of limb segment motion and inherent relationships between gait parameters and body proportions. The findings are discussed in the general framework of space and body movement representation and suggest the existence of a dynamic locomotor body schema used for controlling step length and path estimation.

Adaptation to continuous perturbation of balance: progressive reduction of postural muscle activity with invariant or increasing oscillations of the center of mass depending on perturbation frequency and vision conditions.

We investigated the adaptation of balancing behavior during a continuous, predictable perturbation of stance consisting of 3-min backward and forward horizontal sinusoidal oscillations of the support base. Two visual conditions (eyes-open, EO; eyes-closed, EC) and two oscillation frequencies (LF, 0.2 Hz; HF, 0.6 Hz) were used. Center of Mass (CoM) and Center of Pressure (CoP) oscillations and EMG of Soleus (Sol) and Tibialis Anterior (TA) were recorded. The time course of each variable was estimated through an exponential model. An adaptation index allowed comparison of the degree of adaptation of different variables. Muscle activity pattern was initially prominent under the more challenging conditions (HF, EC and EO; LF, EC) and diminished progressively to reach a steady state. At HF, the behavior of CoM and CoP was almost invariant. The time-constant of EMG adaptation was shorter for TA than for Sol. With EC, the adaptation index showed a larger decay in the TA than Sol activity at the end of the balancing trial, pointing to a different role of the two muscles in the adaptation process. At LF, CoM and CoP oscillations increased during the balancing trial to match the platform translations. This occurred regardless of the different EMG patterns under EO and EC. Contrary to CoM and CoP, the adaptation of the muscle activities had a similar time-course at both HF and LF, in spite of the two frequencies implying a different number of oscillation cycles. During adaptation, under critical balancing conditions (HF), postural muscle activity is tuned to that sufficient for keeping CoM within narrow limits. On the contrary, at LF, when vision permits, a similar decreasing pattern of muscle activity parallels a progressive increase in CoM oscillation amplitude, and the adaptive balancing behavior shifts from the initially reactive behavior to one of passive riding the platform. Adaptive balance control would rely on on-line computation of risk of falling and sensory inflow, while minimizing balance challenge and muscle effort. The results from this study contribute to the understanding of plasticity of the balance control mechanisms under posture-challenging conditions.

Proprioceptive impairment and postural orientation control in Parkinson's disease.

Impairment of postural control is a common consequence of Parkinson's disease (PD). Increasing evidences demonstrate that the pathophysiology of postural disorders in PD includes deficits in proprioceptive processing and integration. However, the nature of these deficits has not been thoroughly examined. We propose to establish a link between proprioceptive impairments and postural deficits in PD using two different experimental approaches manipulating proprioceptive information. In the first one, the subjects stood on a platform that tilted slowly with oscillatory angular movements in the frontal or sagittal planes. The amplitude and frequency of these movements were kept below the semicircular canal perception threshold. Subjects were asked to maintain vertical body posture with and without vision. The orientations of body segments were analyzed. In the second one, the postural control was tested using the tendon-vibration method, which is known to generate illusory movement sensations and postural reactions. Vibrations were applied to ankle muscles. The subject's whole-body motor responses were analyzed from center of pressure displacements. In the first experiment, the parkinsonian patients (PP) were unable to maintain the vertical trunk orientation without vision. Their performances with vision improved, without fully reaching the level of control subjects (CS). In the second experiment, the postural reactions of the PP were similar to those of the CS at the beginning of the perturbation and increased drastically at the end of the perturbation's period as compared to those of CS and could induce fall. These results will bring new concepts to the sensorimotor postural control, to the physiopathology of posture, equilibrium and falls in PD and to the role of basal ganglia pathways in proprioception integration. Nevertheless, in order to assess precisely the role played by sensorimotor integration deficits in postural impairments in PD, further studies establishing the links between clinical features and abnormalities are now required.

EEG correlates of postural audio-biofeedback.

The control of postural sway depends on the dynamic integration of multi-sensory information in the central nervous system. Augmentation of sensory information, such as during auditory biofeedback (ABF) of the trunk acceleration, has been shown to improve postural control. By means of quantitative electroencephalography (EEG), we examined the basic processes in the brain that are involved in the perception and cognition of auditory signals used for ABF. ABF and Fake ABF (FAKE) auditory stimulations were delivered to 10 healthy naive participants during quiet standing postural tasks, with eyes-open and closed. Trunk acceleration and 19-channels EEG were recorded at the same time. Advanced, state-of-the-art EEG analysis and modeling methods were employed to assess the possibly differential, functional activation, and localization of EEG spectral features (power in α, ß, and γ bands) between the FAKE and the ABF conditions, for both the eyes-open and the eyes-closed tasks. Participants gained advantage by ABF in reducing their postural sway, as measured by a reduction of the root mean square of trunk acceleration during the ABF compared to the FAKE condition. Population-wise localization analysis performed on the comparison FAKE - ABF revealed: (i) a significant decrease of α power in the right inferior parietal cortex for the eyes-open task; (ii) a significant increase of γ power in left temporo-parietal areas for the eyes-closed task; (iii) a significant increase of γ power in the left temporo-occipital areas in the eyes-open task. EEG outcomes supported the idea that ABF for postural control heavily modulates (increases) the cortical activation in healthy participants. The sites showing the higher ABF-related modulation are among the known cortical areas associated with multi-sensory, perceptual integration, and sensorimotor integration, showing a differential activation between the eyes-open and eyes-closed conditions.

Sensori-motor integration during stance: time adaptation of control mechanisms on adding or removing vision.

Sudden addition or removal of visual information can be particularly critical to balance control. The promptness of adaptation of stance control mechanisms is quantified by the latency at which body oscillation and postural muscle activity vary after a shift in visual condition. In the present study, volunteers stood on a force platform with feet parallel or in tandem. Shifts in visual condition were produced by electronic spectacles. Ground reaction force (center of foot pressure, CoP) and EMG of leg postural muscles were acquired, and latency of CoP and EMG changes estimated by t-tests on the averaged traces. Time-to-reach steady-state was estimated by means of an exponential model. On allowing or occluding vision, decrements and increments in CoP position and oscillation occurred within about 2s. These were preceded by changes in muscle activity, regardless of visual-shift direction, foot position or front or rear leg in tandem. These time intervals were longer than simple reaction-time responses. The time course of recovery to steady-state was about 3s, shorter for oscillation than position. The capacity of modifying balance control at very short intervals both during quiet standing and under more critical balance conditions speaks in favor of a necessary coupling between vision, postural reference, and postural muscle activity, and of the swiftness of this sensory reweighing process.

Can chronic irritations of the trigeminal nerve cause musculoskeletal disorders?

In this article, five cases of odontogenous dysfunctions and musculoskeletal complaints are presented. A common finding in all patients of this study was that the presence of joint complaints was related to deficits in the corresponding muscular function. These deficits were determined by manual muscle tests as described by Kendall et al. [Muscles - Testing and Function, ed 4. Baltimore, Williams and Wilkins, 1993] and were eliminated immediately by a neural therapeutic test injection into the disturbed dental region. The therapy provided solely aimed to eliminate the odontogenous dysfunction. No other therapeutic measures were carried out with regard to the patients' respective muscle, tendon, or joint complaints.

[Modulation of the functional activity of the acoustic and visual analyzers under conditions of listening to one's own EEG acoustic image of the temporal and occipital cortex areas].

Investigation into the functional activity of the acoustic and visual analyzer has been carried out before and after procedures of listening to one's own EEG of the temporal and occipital cortex areas. It has been shown, that there is a dependence of the dynamics of latent periods of sensomotor response to modality of stimuli and localization of source of the EEG acoustic image. After listening to acoustic image of the temporal EEG, a reduction of sensomotor reaction latency in the acoustic test has been observed. After listening to acoustic image of the occipital EEC, a reduction of sensomotor reaction latency in the visual test has been observed. In the control session after listening to A. Vivaldi's music, no significant shifts of sensomotor reaction latency have been observed. A conclusion has been made that, under conditions of local EEG-acoustic feedback, there is a selective elevation of functional activity of the brain areas used as the EEG-source for acoustic image forming.

Multisensory integration: central processing modifies peripheral systems.

Multisensory integration in humans is thought to be essentially a brain phenomenon, but theories are silent as to the possible involvement of the peripheral nervous system. We provide evidence that this approach is insufficient. We report novel tactile-auditory and tactile-visual interactions in humans, demonstrating that a facilitating sound or visual stimulus that is exactly synchronous with an excitatory tactile signal presented at the lower leg increases the peripheral representation of that excitatory signal. These results demonstrate that during multisensory integration, the brain not only continuously binds information obtained from the senses, but also acts directly on that information by modulating activity at peripheral levels. We also discuss a theoretical framework to explain this novel interaction.

Insular cortex and neuropsychiatric disorders: a review of recent literature.

The insular cortex is located in the centre of the cerebral hemisphere, having connections with the primary and secondary somatosensory areas, anterior cingulate cortex, amygdaloid body, prefrontal cortex, superior temporal gyrus, temporal pole, orbitofrontal cortex, frontal and parietal opercula, primary and association auditory cortices, visual association cortex, olfactory bulb, hippocampus, entorhinal cortex, and motor cortex. Accordingly, dense connections exist among insular cortex neurons. The insular cortex is involved in the processing of visceral sensory, visceral motor, vestibular, attention, pain, emotion, verbal, motor information, inputs related to music and eating, in addition to gustatory, olfactory, visual, auditory, and tactile data. In this article, the literature on the relationship between the insular cortex and neuropsychiatric disorders was summarized following a computer search of the Pub-Med database. Recent neuroimaging data, including voxel based morphometry, PET and fMRI, revealed that the insular cortex was involved in various neuropsychiatric diseases such as mood disorders, panic disorders, PTSD, obsessive-compulsive disorders, eating disorders, and schizophrenia. Investigations of functions and connections of the insular cortex suggest that sensory information including gustatory, olfactory, visual, auditory, and tactile inputs converge on the insular cortex, and that these multimodal sensory information may be integrated there.

How does our brain constitute defense mechanisms? First-person neuroscience and psychoanalysis.

Current progress in the cognitive and affective neurosciences is constantly influencing the development of psychoanalytic theory and practice. However, despite the emerging dialogue between neuroscience and psychoanalysis, the neuronal processes underlying psychoanalytic constructs such as defense mechanisms remain unclear. One of the main problems in investigating the psychodynamic-neuronal relationship consists in systematically linking the individual contents of first-person subjective experience to third-person observation of neuronal states. We therefore introduced an appropriate methodological strategy, 'first-person neuroscience', which aims at developing methods for systematically linking first- and third-person data. The utility of first-person neuroscience can be demonstrated by the example of the defense mechanism of sensorimotor regression as paradigmatically observed in catatonia. Combined psychodynamic and imaging studies suggest that sensorimotor regression might be associated with dysfunction in the neural network including the orbitofrontal, the medial prefrontal and the premotor cortices. In general sensorimotor regression and other defense mechanisms are psychoanalytic constructs that are hypothesized to be complex emotional-cognitive constellations. In this paper we suggest that specific functional mechanisms which integrate neuronal activity across several brain regions (i.e. neuronal integration) are the physiological substrates of defense mechanisms. We conclude that first-person neuroscience could be an appropriate methodological strategy for opening the door to a better understanding of the neuronal processes of defense mechanisms and their modulation in psychoanalytic psychotherapy.

Differential patterns of multisensory interactions in core and belt areas of human auditory cortex.

The auditory cortex is anatomically segregated into a central core and a peripheral belt region, which exhibit differences in preference to bandpassed noise and in temporal patterns of response to acoustic stimuli. While it has been shown that visual stimuli can modify response magnitude in auditory cortex, little is known about differential patterns of multisensory interactions in core and belt. Here, we used functional magnetic resonance imaging and examined the influence of a short visual stimulus presented prior to acoustic stimulation on the spatial pattern of blood oxygen level-dependent signal response in auditory cortex. Consistent with crossmodal inhibition, the light produced a suppression of signal response in a cortical region corresponding to the core. In the surrounding areas corresponding to the belt regions, however, we found an inverse modulation with an increasing signal in centrifugal direction. Our data suggest that crossmodal effects are differentially modulated according to the hierarchical core-belt organization of auditory cortex.

[Measurement method and determination accuracy of the critical frequency of light flashing]. / Metodika izmerenii i tochnost' opredeleniia kriticheskoi chastoty sliianiia svetovykh mel'kanii.

The influence of a measurement method on an accuracy of determining the critical frequency of light flashing was investigated. The least incidental contributing error of measurements was found for the method based to be on progressive approximation with discrete changes of the frequency of light flashing made at the final measurement stage.

[Taurine effects on background impulse activity of the internal geniculate body neurons and mesencephalic inferior tubers of white rats]. / Vliianie taurina na fonovuiu impul'snuiu aktivnost' neironov vnutrennogo kolenchatogo tela nizhnikh bugrov chetverokholmiia belykh krys.

Microelectrophysiological and computer techniques were used in the study of background impulse activity (BIA) of the internal geniculate body (IGB) neurons and mesencephalic inferior tubers (MIT) of white rats. Definite differences were found in BIA by regularity, dynamic types and modality of interimpulse histograms. Mean frequency of MIT neuron discharges was 16-17 Hz and was about 3 times higher than in neurons of the IGB. Intraperitoneal injection of taurin noticeably suppressed neuronal activity in both nuclei. The drug reduced mean frequency of background impulse discharges both in MIT and IGB. Thus, taurin produces primarily suppressing modulating effect on neuronal activity of IGB and MIT.

Neural correlates of action attribution in schizophrenia.

Patients with first-rank symptoms (FRS) of schizophrenia do not experience all of their actions and personal states as their own. FRS may be associated with an impaired ability to correctly attribute an action to its origin. In the present study, we examined regional cerebral blood flow (rCBF) with positron emission tomography during an action-attribution task in a group of patients with FRS. We used a device previously used with healthy subjects that allows the experimenter to modulate the subject's degree of movement control (and thus action attribution) of a virtual hand presented on a screen. In healthy subjects, the activity of the right angular gyrus and the insula cortex appeared to be modulated by the subject's degree of movement control of the virtual hand. In the present study, the schizophrenic patients did not show this pattern. We found an aberrant relationship between the subject's degree of control of the movements and rCBF in the right angular gyrus and no modulation in the insular cortex. The implications of these results for understanding pathological conditions such as schizophrenia are discussed.

A new model of sensorimotor coupling in the development of speech.

We present a computational model that learns a coupling between motor parameters and their sensory consequences in vocal production during a babbling phase. Based on the coupling, preferred motor parameters and prototypically perceived sounds develop concurrently. Exposure to an ambient language modifies perception to coincide with the sounds from the language. The model develops motor mirror neurons that are active when an external sound is perceived. An extension to visual mirror neurons for oral gestures is suggested.