Video games are an exciting part of new media. Although game play has been intensively studied, the underlying neurobiology is still poorly understood. Flow theory is a well-established model ...developed to describe subjective game experience. In 13 healthy male subjects, we acquired fMRI data during free play of a video game and analyzed brain activity based on the game content. In accordance with flow theory, we extracted the following factors from the game content: (i) balance between ability and challenge; (ii) concentration and focus; (iii) direct feedback of action results; (iv) clear goals; and (v) control over the situation/activity. We suggest that flow is characterized by specific neural activation patterns and that the latter can be assessed-at least partially-by content factors contributing to the emergence of flow. Each of the content factors was characterized by specific and distinguishable brain activation patterns, encompassing reward-related midbrain structures, as well as cognitive and sensorimotor networks. The activation of sensory and motor networks in the conjunction analyses underpinned the central role of simulation for flow experience. Flow factors can be validated with functional brain imaging which can improve the understanding of human emotions and motivational processes during media entertainment.
Abstract Impaired fiber bundle connectivity between brain regions is a key neuropathological finding in schizophrenia. Symptom dimensions in schizophrenia can be clustered into factor models. Single ...syndromes have been related to grey and white matter brain structure alterations. We associated all core syndromes of schizophrenia in a single patient group with changes in white matter integrity. Diffusion weighted images (3T MRI) and SAPS/SANS scores were measured in 26 male patients and 26 healthy controls. First, group differences in fractional anisotropy (FA) were calculated with TBSS. Second, core symptom dimensions of schizophrenia were correlated with FA within these altered tracts. We found differences between groups in nine white matter tracts. Hallucinations were positively correlated with FA in the left uncinate fasciculus and left corticospinal tract. Ego-disturbances (passivity phenomena) showed a positive correlation with FA in the right anterior thalamic radiation. Positive formal thought disorders (FTD) corresponded negatively with FA in the right cingulum bundle. Negative symptoms were positively associated with the right anterior thalamic radiation and negatively with the right ventral cingulum bundle. For the first time, we analyzed the whole range of psychopathological factors in one schizophrenia patient group. We could validate our novel results for positive FTD and passivity phenomena by replicating findings for hallucinations and negative symptoms. Only those brain circuits which are most vulnerable at a given time during neurodevelopment are affected by a particular pathological impact (genetic, environmental). This scenario could explain the predominance of particular psychopathological syndromes related to specific white matter anomalies.
Supramodal representation of emotions Klasen, Martin; Kenworthy, Charles A; Mathiak, Krystyna A ...
The Journal of neuroscience,
2011-Sep-21, 2011-09-21, 20110921, Letnik:
31, Številka:
38
Journal Article
Recenzirano
Odprti dostop
Supramodal representation of emotion and its neural substrates have recently attracted attention as a marker of social cognition. However, the question whether perceptual integration of facial and ...vocal emotions takes place in primary sensory areas, multimodal cortices, or in affective structures remains unanswered yet. Using novel computer-generated stimuli, we combined emotional faces and voices in congruent and incongruent ways and assessed functional brain data (fMRI) during an emotional classification task. Both congruent and incongruent audiovisual stimuli evoked larger responses in thalamus and superior temporal regions compared with unimodal conditions. Congruent emotions were characterized by activation in amygdala, insula, ventral posterior cingulate (vPCC), temporo-occipital, and auditory cortices; incongruent emotions activated a frontoparietal network and bilateral caudate nucleus, indicating a greater processing load in working memory and emotion-encoding areas. The vPCC alone exhibited differential reactions to congruency and incongruency for all emotion categories and can thus be considered a central structure for supramodal representation of complex emotional information. Moreover, the left amygdala reflected supramodal representation of happy stimuli. These findings document that emotional information does not merge at the perceptual audiovisual integration level in unimodal or multimodal areas, but in vPCC and amygdala.
Meaning retrieval of a word can proceed fast and effortlessly or can be characterized by a controlled search for candidate lexical items and a subsequent selection process. In the current study, we ...facilitated meaning retrieval by increasing the number of words that were related to the final target word in a triplet (e.g., lion-stripes-tiger). To induce higher search and selection demands, we presented ambiguous words as targets (i.e., homonyms like ball) in half of the trials. Hereby, the dominant (game), low-frequent (dance), or both meanings of the homonym were primed. Participants performed a relatedness judgment during functional magnetic resonance imaging. Activation in a bilateral network (angular gyrus, rostromedial prefrontal cortex) increased linearly with multiple related primes, whereas the posterior left inferior prefrontal cortex (pLIPC) showed the reverse activation pattern for unambiguous trials. When homonyms served as targets, pLIPC responded strongest when both meanings or low-frequent concepts were addressed. Additional anterior left inferior prefrontal cortex activation was observed for the latter trials only. The data support an interaction between 2 distinct cerebral networks that can be linked to automatic bottom-up support and top-down control during meaning retrieval. They further imply a functional specialization of the LIPC along an anterior-posterior dimension.
We investigated processing of metaphoric sentences using event-related functional magnetic resonance imaging (fMRI). Seventeen healthy subjects (6 female, 11 male) read 60 novel short German sentence ...pairs with either metaphoric or literal meaning and performed two different tasks: judging the metaphoric content and judging whether the sentence has a positive or negative connotation. Laterality indices for 8 regions of interest were calculated: Inferior frontal gyrus (opercular part and triangular part), superior, middle, and inferior temporal gyrus, precuneus, temporal pole, and hippocampus. A left lateralised network was activated with no significant differences in laterality between the two tasks. The lowest degree of laterality was found in the temporal pole. Other factors than metaphoricity per se might trigger right hemisphere recruitment. Results are discussed in the context of lesion and hemifield studies.
Self-concept is deeply affected in schizophrenia. Positive symptoms in particular are related to disturbed self/other distinctions. The neural networks underlying self-evaluation in schizophrenia ...have barely been investigated. The study reported here involved 13 patients with schizophrenia and 13 matched controls. During functional MRI, participants decided in three conditions whether the presented positive and negative personality traits characterized themselves, an intimate person, or included a certain letter. Based on the responses, each experimental condition was designed using a flexible factorial model. Controls and patients showed a similar behavioral pattern during self-evaluation, with group comparison revealing decreased activation in patients in the left inferior temporal gyrus and both temporal poles during self-ascription of traits, and in the anterior medial prefrontal cortex during evaluation of an intimate person. In patients, positive symptoms correlated positively with brain activation in the left parahippocampus during trait self-ascription. Hence, while evaluating themselves, schizophrenia patients revealed decreased activation in areas related to self-awareness overlapping with networks involved in theory of mind, empathy and social knowledge. Moreover, patients' brain activation during self-reflection was affected by the current positive symptomatology. The close interaction between self and other highlights the clinical and social relevance of self-processing deficits in schizophrenia.
Abstract Ego disturbances in schizophrenia might be caused by a failure of the efference copy mechanism, which compares efferent with reafferent signals and attenuates the sensory consequences of ...self-produced movements. We carried out a functional magnetic resonance imaging study in which 16 patients with schizophrenia and 16 healthy matched controls were studied while performing both intentional and unintentional continuous hand movements in two consecutive experiments. We periodically varied the delay of visual feedback to create a sensory-motor discrepancy. Exclusively for intentional movements the activation pattern of the inferior frontal gyrus (IFG) in patients was opposite to that of controls: less attenuated during time-congruent feedback and less activated during time-incongruent feedback. Additionally, several functional connections within the mismatch detection network (IFG with insula, putamen, medial orbitofrontal cortex) were affected. Also, activity of the dysconnected orbitofrontal cortex was correlated with ego disturbance in patients. We discuss that in healthy individuals the IFG might enable a distinction between self and non-self using time-characteristics of feedback, whereas in patients this sensory mismatch detection appears to be altered. Moreover, due to the dysconnectivity of the IFG, the efferent and reafferent signal exchange between perceptual and motor areas seems to be affected. This might cause self-monitoring deficits in patients, phenomena that contribute to the emergence of ego disturbances.
A main feature of schizophrenic thought and language disturbance is concretism, the inability to understand the figurative meaning of proverbs and metaphors. Although this is routinely tested during ...clinical interview, its neural basis is unknown.
We investigated processing of metaphoric sentences with functional magnetic resonance imaging (fMRI) in 12 patients with schizophrenia and 12 control subjects. Stimuli consisted of 60 novel short sentences with either metaphoric or literal meaning presented visually, intersparsed by a low level baseline (grey background). Subjects read these sentences silently and judged by button press whether they had a positive or negative connotation.
Reading metaphors in contrast to literal sentences revealed signal changes in the left inferior frontal gyrus in the control subjects (BA 45/47) and an area 3 cm dorsal to that in the patients (BA 45). Only activation in this area was negatively correlated with the severity of concretism rated with the PANSS. Comparison between groups for the contrast metaphors vs. low level baseline revealed stronger signal changes in the control group in the right superior/middle temporal gyrus (BA 39) and the left inferior frontal gyrus (BA 45) in the patients.
The results in the control subjects are in line with studies showing an involvement of the left inferior frontal and right lateral temporal cortex during context processing. Failure to recruit these areas in the patients may underlie schizophrenic concretism.
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