Semantic categorization in the human brain: spatiotemporal dynamics revealed by magnetoencephalography

We examined the cortical representation of semantic categorization using magnetic source imaging in a task that revealed both dissociations among superordinate categories and associations among different base-level concepts within these categories. Around 200 ms after stimulus onset, the spatiotemporal correlation of brain activity elicited by base-level concepts was greater within than across superordinate categories in the right temporal lobe. Unsupervised clustering of data showed similar categorization between 210 and 450 ms mainly in the left hemisphere. This pattern suggests that well-defined semantic categories are represented in spatially distinct, macroscopically separable neural networks, independent of physical stimulus properties. In contrast, a broader, task-required categorization (natural/man-made) was not evident in our data. The perceptual dynamics of the categorization process is initially evident in the extrastriate areas of the right hemisphere; this activation is followed by higher-level activity along the ventral processing stream, implicating primarily the left temporal lobe.     

The early origins of goal attribution in infancy

We contrast two positions concerning the initial domain of actions that infants interpret as goal-directed. The 'narrow scope' view holds that goal-attribution in 6- and 9-month-olds is restricted to highly familiar actions (such as grasping). The cue-based approach of the infant's 'teleological stance', however, predicts that if the cues of equifinal variation of action and a salient action effect are present, young infants can attribute goals to a 'wide scope' of entities including unfamiliar human actions and actions of novel objects lacking human features. It is argued that previous failures to show goal-attribution to unfamiliar actions were due to the absence of these cues. We report a modified replication of Woodward (1999) showing that when a salient action-effect is presented, even young infants can attribute a goal to an unfamiliar manual action. This study together with other recent experiments reviewed support the 'wide scope' approach indicating that if the cues of goal-directedness are present even 6-month-olds attribute goals to unfamiliar actions.     

Understanding mass allegations of satanist child abuse in early modern Sweden: demographic data relevant to the Rättvik outbreak of 1670-1671

Demographic characteristics of 79 women who were accused of satanist child abductions in the parish of R?ttvik, Sweden, in 1670-1671; 53 adults who promoted such accusations by bringing children to interrogations; and samples from the general population of R?ttvik were compared. Results indicate that men were more likely to promote allegations of satanism than women and that these men were more likely to be married than the average R?ttvik male. Promoters of allegations were older than average parishioners, and land-owning people who were involved in the panic owned more land than landowners who were not involved. People who were involved in the panic knew less about Luther's catechism than members of the general population. It is suggested that most of these findings may reflect a tendency of people who lived in the proximity of children to become involved in the panic.     

Teleological reasoning in infancy: the nai;ve theory of rational action

Converging evidence demonstrates that one-year-olds interpret and draw inferences about other's goal-directed actions. We contrast alternative theories about how this early competence relates to our ability to attribute mental states to others. We propose that one-year-olds apply a non-mentalistic interpretational system, the 'teleological stance' to represent actions by relating relevant aspects of reality (action, goal-state and situational constraints) through the principle of rational action, which assumes that actions function to realize goal-states by the most efficient means available. We argue that this early inferential principle is identical to the rationality principle of the mentalistic stance - a representational system that develops later to guide inferences about mental states.     

Memory bias for faces that are perceived as hostile by crime victims with acute post-traumatic stress disorder

The present study tested, and found support for, the hypotheses that crime victims with acute post-traumatic stress disorder have: (i) a general memory impairment for faces; and (ii) a memory bias for faces that they perceive as hostile, even when these faces are not arranged to show any hostile face expressions. It is suggested that crime victims with acute post-traumatic stress disorder perform worse on recognition memory due to impaired concentration, and that they allocate their limited attentional resources to the detection of hostility in others in order to avoid being victimized again. This produces a memory bias for perceived hostility even in relatively innocuous everyday interactions with others, which contributes to maintaining the sense of serious current threat that characterizes post-traumatic stress disorder.     

Long-term, non-specific spinal pain: reliable and valid subgroups of patients

The aim of this study was to identify reliable and valid subgroups of spinal pain patients, using data from the Swedish version of the Multidimensional Pain Inventory (MPI-S). A second aim was to test the generalisability of the three patient profiles described in earlier studies on the MPI ("adaptive coper", "dysfunctional" and "interpersonally distressed" patients). The study base consisted of two samples of individuals suffering from long-term, non-specific spinal pain and the results were validated across these samples. Cluster analysis was used to detect distinct groups of patients and the validity of these subgroups was evaluated on variables not used to generate the cluster solution. One subgroup was characterised by lower pain severity, lower interference with everyday activities, lower affective distress and higher life control than the other two subgroups. This patient profile was similar to the MPI adaptive coper patients. A second subgroup resembled the dysfunctional patient profile, thus displaying a worse adjustment to chronic pain than the AC patients. The third patient group reported significantly lower levels of social support from "significant others" than the other subgroups. This patient profile was similar to that of the interpersonally distressed patient group. Taken together, the results support the reliability, validity and generalisability of three subgroups of chronic pain patients derived from the MPI-S.     

Cognitive processing in literate and illiterate subjects: a review of some recent behavioral and functional neuroimaging data

The study of illiterate subjects, which for specific socio-cultural reasons did not have the opportunity to acquire basic reading and writing skills, represents one approach to study the interaction between neurobiological and cultural factors in cognitive development and the functional organization of the human brain. In addition the naturally occurring illiteracy may serve as a model for studying the influence of alphabetic orthography on auditory-verbal language. In this paper we have reviewed some recent behavioral and functional neuroimaging data indicating that learning an alphabetic written language modulates the auditory-verbal language system in a non-trivial way and provided support for the hypothesis that the functional architecture of the brain is modulated by literacy. We have also indicated that the effects of literacy and formal schooling is not limited to language related skills but appears to affect also other cognitive domains. In particular, we indicate that formal schooling influences 2D but not 3D visual naming skills. We have also pointed to the importance of using ecologically relevant tasks when comparing literate and illiterate subjects. We also demonstrate the applicability of a network approach in elucidating differences in the functional organization of the brain between groups. The strength of such an approach is the ability to study patterns of interactions between functionally specialized brain regions and the possibility to compare such patterns of brain interactions between groups or functional states. This complements the more commonly used activation approach to functional neuroimaging data, which characterize functionally specialized regions, and provides important data characterizing the functional interactions between these regions.     

Visual perspective taking for avatars in a Simon task

In modern digital applications, users often interact with virtual representations of themselves or others, called avatars. We examined how these avatars and their perspectives influence stimulus–response compatibility in a Simon task. Participants responded to light/dark blue stimuli with left/right key presses in the presence of a task-irrelevant avatar. Changes in stimulus–response compatibility were used to quantify changes in the mental representation of the task and perspective taking toward this avatar. Experiments 1 and 2 showed that perspective taking for an avatar occurred in orthogonal stimulus–response mappings, causing a compatibility effect from the avatar’s point of view. In the following two experiments we introduced a larger variety of angular disparities between the participant and avatar. In Experiment 3, the Simon effect with lateralized stimulus positions remained largely unaffected by the avatar, pointing toward an absence of perspective taking. In Experiment 4, after avatar hand movements were added in order to strengthen the participants’ sense of agency over the avatar, a spatial compatibility effect from the avatar’s perspective was observed again, and hints of the selective use of perspective taking on a trial-by-trial basis were found. Overall, the results indicate that users can incorporate the perspective of an avatar into their mental representation of a situation, even when this perspective is unnecessary to complete a task, but that certain contextual requirements have to be met.     

Learning to ignore the mask in texture segmentation tasks

Although traditionally texture segmentation has been regarded as an automatic, preattentive process, participants confronted with texture segmentation in experimental settings (i.e., with brief presentation time and subsequent masking) are initially unable to perform the task. According to perceptual learning concepts, participants must learn to fine-tune their sensory channels before perception improves under restricted viewing conditions. The present article proposes an alternative perspective that emphasizes the role of the mask. Four experiments showed that the amount of observed learning depends on the structural and temporal homogeneity or heterogeneity of the mask. The authors suggest that learning consists of separating the task-relevant signal stemming from the texture from the task-irrelevant signal of the mask and of ignoring the mask.