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.     

Low alpha power (7.5–9.5 Hz) changes during positive and negative affective learning

There is evidence that the positive and the negative word lists of the Affective Auditory Verbal Learning Test (AAVL) are useful with regard to mood induction. To date, however, changes in brain activation, as indicated by quantitative electroencephalographic recording, have not been examined. Thus, changes in low alpha power (7.5-9.5 Hz) were examined during and after completion of the positive or the negative learning list of the AAVL among 37 undergraduate men and women. Three primary findings from the study include the following: (1) Previously reported recall patterns were replicated; (2) participants who completed the negative list reported a significant decline in mood state at the end of the session; and (3) participants who completed the negative word list evidenced a significant reduction in low alpha power (in comparison with baseline) within the parietal regions. The findings noted above are seemingly counter to contemporary theories of mood regulation (i.e., asymmetrical changes in anterior activity, rather than changes in parietal regions). Although the AAVL may have limited utility as a tool for mood induction, it may serve as a functional tool for examination of the cerebral processes associated with affective verbal memory.     

Strategic aspects of numerosity judgment: the effect of task characteristics

In previous investigations we documented that people use several strategies to determine different numerosities of blocks that are presented in a square grid. One of these strategies is the clever subtraction strategy, wherein the number of empty squares in the grid is subtracted from the total number of squares in the grid. In the present study we investigated participants' flexibility in strategy use when varying the shape of the grid. Analysis of the results in terms of the theoretical framework of Lemaire and Siegler (1995) regarding strategic change shows that this contextual variable affected the frequency, execution time, and accuracy of subjects' use of the subtraction strategy. The usefulness of this framework for analyzing the nature of the adaptation to contextual variations is discussed. From a methodological point of view, this study documents the potential of Beem's (1993, 1999) segmented linear regression models for assessing subjects' strategy use in cognitive tasks.     

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.     

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.