The orienting response,and future directions of its development

The orienting response (OR) is a specific behavioral act directed towards extraction of information from the environment. Head and eye movements represent only the tip of the iceberg of internal responses, which includes vascular modifications, EEG changes, and event-related potentials. Two mechanisms of the OR have to be differentiated: voluntary and involuntary. In the event-related potential, such a differentiation is expressed in mismatch negativity (involuntary effect) and processing negativity (voluntary effect). Single unit studies have shown that hippocampal neurones are simulating specific features of the OR as a response to novelty. Repeated presentation of stimuli results in a selective habituation of novelty detectors in hippocampus and of the OR. The trace of a standard stimulus formed at the level of hippocampal neurones matches the features of the standard stimulus and can be called a “neuronal model of the stimulus.” The OR is triggered by mismatch between the test stimulus and the elaborated neuronal model, and is activated by verbal instruction, by reinforcement during the initial stage of conditioned reflex elaboration, and by differentiation of signal and non-signal stimuli. A promising new area of practical application of the OR lies in the evaluation of a corridor of optimal functional state for efficient computer-based learning. Registration of the OR and defensive responses can be used for an objective evaluation of the functional state of the student, or, in a wider sense, of the industrial operator. New avenues of OR research are opened by recent techniques that isolate single-trial event related potentials, and their correlation with autonomic and behavioral manifestations of the OR. The combination of single unit recording with such isolated event related potentials can elucidate the neuronal basis of OR generation. Intracellular recording combined with dye injection can be used for analysis of the synaptic contacts involved in generation of the OR. Integration of macro and micro levels of OR organization can be achieved in a computerized model that can be used for simulation and planning of experiments. A step-by-step improvement of the model will accumulate knowledge about the OR as an important mechanism of information processing.     

MULTIDIMENSIONAL SCALING OF LARGE CHROMATIC DIFFERENCES BY NORMAL AND COLOR-DEFICIENT SUBJECTS

The following two articles offer a glimpse at current experimental psychology in the Soviet Union, normally screened from the English-speaking world by all but impenetrable language barriers. The accompanying Commentary by Tarow Indow helps place these contributions in the framework of contemporary work on the psychophysics of color perception.   Abstract —
Fifteen normal trichromatic subjects, two protanopes, and two deuteranopes judged pairs of successively presented foveal color stimuli. Multidimensional scaling of the data yielded estimates of a three-dimensional space with axes interpreted as red–green, blue-yellow, and white-black. For color-deficient subjects, the average radius of the space differed from that of normals, being smaller for the protanopes and larger for the deuteranopes. For both types of color deficiency, the blue-yellow axis was stretched relative to the red-green, more strongly in the protanopes. The findings are taken to support the generality of a "spherical" model.     

Multidimensional scaling of schematically represented faces based on dissimilarity estimates and evoked potentials of differences amplitudes

This study researches the input of the cerebral occipital and temporal cortex in the analysis of facial configuration and expressive characteristics. Analysis is based on the construction of a spherical model for the differentiation of schematically presented faces with quantitatively altering curvature of the mouth and brows. The model is designed using the method of multidimensional scaling of the dissimilarity judgments between stimuli (faces) and the amplitude of evoked potentials of differences (EPD) between abrupt stimulus changes recorded from the occipital and posterior temporal cortex. Analysis of the structure of the spherical model of facial differentiation depending on the electrode site and the latency of the EPD component within the duration of 120-240 ms has demonstrated that the activity of the occipital and posterior temporal cortex of the right hemisphere is associated with the emotional characteristics of the presented face, whereas facial configuration is reflected in the activation of both posterior temporal cortex and the occipital cortex of the left hemisphere. At all electrode sites maximum information of the emotional expression and configuration is represented in inter-peak amplitude P120-N180. With increasing latency there is increased distortion of the structure of differences in the spherical model of schematically presented faces, which is interpreted as an attenuation of electrical activity associated with the analysis of the emotional expression, which occurs more rapidly than configuration analysis.     

Comorbidity in schizophrenia: A prognostic study of personality disorders in recovered and non-recovered schizophrenia patients

Symptoms and outcome in schizophrenia are heterogeneous. Part of the variation in outcome might be due to the coexistence of other forms of psychopathology. In the present study the prevalence of personality disorders in a group of recovered and non-recovered schizophrenia patients was focused to examine the prognostic implications of comorbidity for the outcome of the disorder. The results showed no significant differences in prevalence of personality disorders in the two groups at first admission to the hospital, but the difference at the time of interview was close to significance. Emotional and conduct difficulties in adolescence were significantly more prevalent in the non-recovered group. Schizoid features and emotional and conduct disorders in childhood were also more often reported among the non-recovered subjects. The results confirm that comorbidity contributes to the variation in outcome for schizophrenia patients, but does not confirm its prognostic significance.     

Relationship problems and extradyadic romantic and sexual activity in a web‐sample of Norwegian men and women

The purpose of this paper is to describe the prevalence of self‐reported types of extradyadic romantic and sexual activity among adult Norwegians and to explore the role of infidelity in breaking up a permanent relationship. The results are based on 1,001 web interviews with persons ranging in age from 18 to 67 years. The majority of respondents reported having engaged in some kind of extradyadic romantic and/or sexual activity. Forty‐five percent of the women and 39% of the men claimed they had experienced a previous breakup from a marriage or cohabiting relationship. Among those aged 50 years or older, the most important reasons for breaking up a previous relationship were infidelity (38%) and lost love (38%). More men (44%) than women (33%) reported infidelity. Respondents younger than 50 years were more motivated by boredom. Among respondents below the age of 50 years, the most frequently reported reasons for considering termination of a present relationship were quarreling (37%), poor sex life (29%), and “other” reasons (25%). Accordingly, infidelity was not identified as an essential factor for considering a breakup from the present relationship.     

Role of cross-slipping in formation of edge dislocations in heteroepitaxial systems GeSi-on-Si(001) and Ge-on-InGaAs/GaAs

Edge misfit dislocations (MDs) formed as result of reactions between 60° glissile threading dislocations and 60° MDs lying on an intersecting glide plane were found in strained GeSi-on-Si(001) and Ge-on-InGaAs/GaAs films. It was demonstrated that dislocations penetrating from the InGaAs buffer layer to the strained Ge film can provoke formation of not only 60° MDs, but also edge MDs on the interface even at minor mismatch of the lattice parameters of the film and the InGaAs/GaAs virtual substrate.     

Experimental observation of the dislocation walls in heterostructures with two interfaces: Ge/Ge0.5Si0.5 10 nm/Si(001) as an example

High-resolution electron microscopy (HREM) at the atomic scale has been applied to study the edge dislocation redistribution between interfaces in Ge/Ge_0.5Si_0.5/Si(0?0?1) heterostructures. Our results provide a direct explanation that plastic relaxation of the GeSi buffer layer proceeds owing to motion of Lomer-type dislocation complexes consisting of a pair of complementary 60° dislocations with the ends of the {1?1?1} extra planes being located at a distance of ~2–12 interplanar spacings from each other. It is demonstrated that edge dislocations belonging to the upper and lower interfaces become arranged one under the other and dislocation walls are formed. The distributions of tension and compression in the [0?0?1] direction between two edge dislocations, obtained by processing the HREM image, testify to superposition of strain fields.     

The semantic component of the evoked potential of differentiation

This work analyzes data from recordings of (occipital and temporal) cortical evoked potentials (called evoked potentials of differentiation (EPD) occurring in humans in response to an abrupt substitution of stimuli. As stimuli we used three groups of words: the names of the ten basic colors taken from Newton's color circle; the names of seven basic emotions forming Shlossberg's circle of emotions; and seven nonsense words comprised of random combinations of letters. Within each group of word stimuli we constructed a matrix of the differences between the amplitudes of mid-latency components of EPD for each pair of words. This matrix was analyzed using the method of multidimensional scaling. As a result of this analysis we were able to distinguish the semantic and configurational components of EPD amplitude. The semantic component of EPD amplitude was evaluated by comparing structure of the data obtained to the circular structures of emotion and color names. The configurational component was evaluated on the basis of the attribute of word length (number of letters). It was demonstrated that the semantic component of the EPD can only be detected in the left occipital lead at an interpeak amplitude of P120-N180. The configurational component is reflected in the occipital and temporal leads to an identical extent, but only in the amplitude of a later (N180-P230) component of the EPD. The results obtained are discussed in terms of the coding of categorized, configurational, and semantic attributes of a visual stimulus.     

The Color-Vision Approach to Emotional Space: Cortical Evoked Potential Data

A framework for accounting for emotional phenomena proposed by Sokolov and Boucsein (2000) employs conceptual dimensions that parallel those of hue, brightness, and saturation in color vision. The approach that employs the concepts of emotional quality. intensity, and saturation has been supported by psychophysical emotional scaling data gathered from a few trained observers. We report cortical evoked potential data obtained during the change between different emotions expressed in schematic faces. Twenty-five subjects (13 male, 12 female) were presented with a positive, a negative, and a neutral computer-generated face with random interstimulus intervals in a within-subjects design, together with four meaningful and four meaningless control stimuli made up from the same elements. Frontal, central, parietal, and temporal ERPs were recorded from each hemisphere. Statistically significant outcomes in the P300 and N200 range support the potential fruitfulness of the proposed color-vision-model-based approach to human emotional space.