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[english] Teaching in medical psychology aims at establishing an understanding of the relationships between psychological functions and bodily reactions and of the relevance of these interactions for the development and maintenance of diseases. To illustrate these relationships, a psychophysiology practical was introduced in the first semester. Students performed practical 30-minute exercises in groups of four on the basis of comprehensive written instructions. The following topics were covered: (1) stress (dependent variable: heart rate), (2) "lie detection" (dependent variable: skin conductance response), (3) biofeedback (dependent variable: skin temperature), and (4) electroencephalogram (dependent variable: amplitude in the four classical frequency bands). The practical exercises were complemented by theoretical group work and a summary of the results of the exercises. Students evaluated the practical positively. It was considered a benefit to the course, and the self-rated knowledge in the area of psychophysiology increased significantly. These results, as well as our experiences during the practical, have reinforced our decision to establish a psychophysiology practical as part of the medical psychology/medical sociology course.[german] Die Vermittlung der Zusammenhänge zwischen psychologischen Funktionen und körperlichen Veränderungen sowie deren Relevanz für die Entstehung und Aufrechterhaltung von Krankheiten stellt ein zentrales Ziel der Ausbildung in Medizinischer Psychologie dar. Zur Veranschaulichung dieser Zusammenhänge führten wir ein Psychophysiologie-Praktikum im ersten vorklinischen Semester ein. Die Studierenden führten in Vierergruppen mit Hilfe ausführlicher schriftlicher Instruktionen jeweils ca. 30 Minuten andauernde praktische Übungen durch, die die folgenden Themen behandelten: (1) Stress (abhängige Variable: Herzrate), (2) "Lügendetektor" (abhängige Variable: Hautleitwertsreaktionen), (3) Biofeedback (abhängige Variable: Hauttemperatur) und (4) Elektroenzephalogramm (abhängige Variable: Amplituden der vier klassischen Frequenzbänder). Die praktischen Übungen wurden durch theoretische Gruppenarbeiten und einen Termin zur Zusammenfassung der Ergebnisse der Übungen ergänzt. Die studentische Evaluation des Praktikums war durchweg positiv. So wurde das Praktikum als Bereicherung des Kurses angesehen, und der selbstbeurteilte Kenntnisstand auf dem Gebiet der Psychophysiologie zeigte eine signifikante Verbesserung. Diese Ergebnisse sowie unsere Eindrücke während des Praktikums bekräftigten unseren Entschluss, ein Psychophysiologie-Praktikum als Teil des Kurses der Medizinischen Psychologie und Medizinischen Soziologie fest zu etablieren.

Information integration across different sensory modalities contributes to object recognition, the generation of associations and long-term memory representations. Here, we used functional magnetic resonance imaging adaptation to investigate the presence of sensory integrative effects at cortical levels as early as nonprimary auditory and extrastriate visual cortices, which are implicated in intermediate stages of object processing. Stimulation consisted of an adapting audiovisual stimulus S1 and a subsequent stimulus S2 from the same basic-level category (e.g., cat). The stimuli were carefully balanced with respect to stimulus complexity and semantic congruency and presented in four experimental conditions: (1) the same image and vocalization for S1 and S2 , (2) the same image and a different vocalization, (3) different images and the same vocalization, or (4) different images and vocalizations. This two-by-two factorial design allowed us to assess the contributions of auditory and visual stimulus repetitions and changes in a statistically orthogonal manner. Responses in visual regions of right fusiform gyrus and right lateral occipital cortex were reduced for repeated visual stimuli (repetition suppression). Surprisingly, left lateral occipital cortex showed stronger responses to repeated auditory stimuli (repetition enhancement). Similarly, auditory regions of interest of the right middle superior temporal gyrus and sulcus exhibited repetition suppression to auditory repetitions and repetition enhancement to visual repetitions. Our findings of crossmodal repetition-related effects in cortices of the respective other sensory modality add to the emerging view that in human subjects sensory integrative mechanisms operate on earlier cortical processing levels than previously assumed. [ABSTRACT FROM AUTHOR]

In addition to reward- and craving-related processes, habitual mechanisms play an important role in addiction. While the dorsal striatum has been proposed to code for the motivational state of habitual drug-seeking actions, the neural underpinnings of the corresponding drug-taking skills and action knowledge remain poorly understood. We used functional magnetic resonance imaging (fMRI) and a behavioral orientation affordance paradigm to investigate the neural and behavioral correlates of automatized drug-taking actions in nicotine dependence. Smokers exhibited higher fMRI activations than nonsmokers when viewing smoking-related but not when viewing control images. These group differences in fMRI activations were located not only in brain regions associated with craving and habitual learning (left ventral and dorsal striatum, dorsolateral prefrontal cortex, insula, uncus, medial frontal gyrus, right subcallosal gyrus, and bilateral parahippocampal gyrus), but also in a network of brain regions which has been strongly implicated in the encoding of action knowledge and tool use skills (bilateral premotor cortex, left superior parietal lobule, and right lateral cerebellum). A behavioral affordance reaction-time task indicated that smokers, but not nonsmokers, showed an automatized responsiveness to smoking paraphernalia similar to everyday objects. Moreover, smokers showed strong intercorrelations between fMRI activations in tool use-related brain regions, behavioral responsiveness to smoking-related cues, and severity of nicotine dependence. Apparently smoking-related action representations in smokers are stored in brain regions typically representing tool use skills and action knowledge. Most importantly, cortical and behavioral correlates of the respective drug-taking skills vary with the individual degree of nicotine dependence. [ABSTRACT FROM AUTHOR]

In complex natural environments, auditory and visual information often have to be processed simultaneously. Previous functional magnetic resonance imaging (fMRI) studies focused on the spatial localization of brain areas involved in audiovisual (AV) information processing, but the temporal characteristics of AV information flow in these regions remained unclear. In this study, we used fMRI and a novel information-theoretic approach to study the flow of AV sensory information. Subjects passively perceived sounds and images of objects presented either alone or simultaneously. Applying the measure of mutual information, we computed for each voxel the latency in which the blood oxygenation level-dependent signal had the highest information content about the preceding stimulus. The results indicate that, after AV stimulation, the earliest informative activity occurs in right Heschl's gyrus, left primary visual cortex, and the posterior portion of the superior temporal gyrus, which is known as a region involved in object-related AV integration. Informative activity in the anterior portion of superior temporal gyrus, middle temporal gyrus, right occipital cortex, and inferior frontal cortex was found at a later latency. Moreover, AV presentation resulted in shorter latencies in multiple cortical areas compared with isolated auditory or visual presentation. The results provide evidence for bottom-up processing from primary sensory areas into higher association areas during AV integration in humans and suggest that AV presentation shortens processing time in early sensory cortices. [ABSTRACT FROM AUTHOR]

The cortical integration of auditory and visual features is crucial for efficient object recognition. Previous studies have shown that audiovisual (AV) integration is affected by where and when auditory and visual features occur. However, because relatively little is known about the impact of what is integrated, we here investigated the impact of semantic congruency and object familiarity on the neural correlates of AV integration. We used functional magnetic resonance imaging to identify regions involved in the integration of both (congruent and incongruent) familiar animal sounds and images and of arbitrary combinations of unfamiliar artificial sounds and object images. Unfamiliar object images and sounds were integrated in the inferior frontal cortex (IFC), possibly reflecting learning of novel AV associations. Integration of familiar, but semantically incongruent combinations also correlated with IFC activation and additionally involved the posterior superior temporal sulcus (pSTS). For highly familiar semantically congruent AV pairings, we again found AV integration effects in pSTS and additionally in superior temporal gyrus. These findings demonstrate that the neural correlates of object-related AV integration reflect both semantic congruency and familiarity of the integrated sounds and images. [ABSTRACT FROM AUTHOR]

In complex natural environments, auditory and visual information often have to be processed simultaneously. Previous functional magnetic resonance imaging (fMRI) studies focused on the spatial localization of brain areas involved in audiovisual (AV) information processing, but the temporal characteristics of AV information flow in these regions remained unclear. In this study, we used fMRI and a novel information-theoretic approach to study the flow of AV sensory information. Subjects passively perceived sounds and images of objects presented either alone or simultaneously. Applying the measure of mutual information, we computed for each voxel the latency in which the blood oxygenation level-dependent signal had the highest information content about the preceding stimulus. The results indicate that, after AV stimulation, the earliest informative activity occurs in right Heschl's gyrus, left primary visual cortex, and the posterior portion of the superior temporal gyrus, which is known as a region involved in object-related AV integration. Informative activity in the anterior portion of superior temporal gyrus, middle temporal gyrus, right occipital cortex, and inferior frontal cortex was found at a later latency. Moreover, AV presentation resulted in shorter latencies in multiple cortical areas compared with isolated auditory or visual presentation. The results provide evidence for bottom-up processing from primary sensory areas into higher association areas during AV integration in humans and suggest that AV presentation shortens processing time in early sensory cortices.