Autism spectrum traits in normal individuals : a preliminary VBM analysis

In light of the new DSM-5 autism spectrum disorders diagnosis in which the autism spectrum reflects a group of neurodevelopmental disorders existing on a continuum from mild to severe expression of autistic traits, and recent empirical findings showing a continuous distribution of autistic traits in the general population, our voxel based morphometry study compares normal individuals with high autistic traits to normal individuals with low autistic traits. We hypothesize that normal individuals with high autistic traits in terms of empathizing and systemizing [high systemizing (HS)/low empathizing (LE)] share brain irregularities with individuals that fall within the clinical autism spectrum disorder. We find differences in several social brain network areas between our groups. Specifically, we find increased gray matter (GM) volume in the orbitofrontal cortex, the cuneus, the hippocampus and parahippocampus and reduced GM volume in the inferior temporal cortex, the insula, and the amygdala in our HS/LE individuals relative to our HE/LS (low autistic traits in terms of empathizing and systemizing) individuals

Outstanding questions concerning the regulation of enhancement devices

The authors (Maslen et al., 2014) propose to regulate cognitive enhancement devices (CEDs) as medical devices. Extending medical device regulations to CEDs raises some important questions that need to be adequately addressed before it makes sense to pursue this path. A first problem concerns the definition of ‘cognitive enhancement’ and ‘CEDs’. Where does treatment end and enhancement begin? Secondly, since most CEDs such as neurofeedback and transcranial direct current stimulation are currently performed by non-medical health care providers, how will this regulation impact the current practice, and which requirements need to be put in place to regulate their use? Thirdly, distributive justice issues present an obvious ethical limitation. Fourthly, if CEDs are indeed prescribed off-label similar to the off-label prescription of psychopharmacological enhancers by MDs, this will pose problems regarding a lack of sufficient knowledge and expertise due to the highly specialized nature of CEDs. And finally, are we faced with unnecessary worries and unrealistic hopes when it comes to CEDs? In sum, we propose to regulate them regarding product safety and restrict them to competent adult use including professional oversight where indicated

Is cheater/cooperator detection an in-group phenomenon? Some preliminary findings

Whereas predictive detection of (non-)cooperative intentions among humans is well-documented, virtually nothing is known about the cross-cultural extent of this possibly evolved social intuition. In this study we asked Caucasian participants to judge Japanese subjects who played a trust game in which they either fairly divided the money (sharer) or kept the entire sum (non-sharer). After watching 5-seconds videotapes taken around decision Caucasian subjects were able to discriminate non-sharing and sharing Japanese targets slightly above chance level (51.71%). The non-sharers accuracy rate was 52.32% and the sharers accuracy rate was 51.10%, but significant higher than would be expected from randomly guessing alone. This preliminary finding suggests that successful cheater/cooperator detection is not limited to own-culture targets and questions the in-group nature of this social intuition

Putting Humpty Dumpty Back Together: Pricing in Anticommons Property Arrangements

Recently, a new theory has drawn considerable attention in the literature on common property. A number of scholars have pointed to the danger of excessive propertization in the context of what are termed anticommons property regimes. Although this theory has found its way into numerous legal and economic applications, the empirical and cognitive foundations of the theory of fragmentation remain unexplored. Based on experimental data, this Article conducts an investigation into the social and personal processes involved in the anticommons. The results confirm the theoretical proposition that anticommons deadweight losses increase with the degree of complementarity between individual parts and with the degree of fragmentation. Our study also provides three novel insights into the problem of fragmentation. First, the data illustrate that individual right holders base their reservation price on a proportion of the expected surplus of the bundler-purchaser, disregarding the objective value of the resource. Second, the experiments suggest that uncertainty amplifies the anticommons pricing effect. Individual right holders ignore the expected value of the purchaser’s project, and instead focus on the upper range of profitability and surplus. Willingness to accept is anchored onto a proportion of the maximum profitability, rather than a proportion of the expected benefits of the project. Finally, throughout the experiment reservation prices seem to be consistently lower in cases where there exists large uncertainty within the range of positive outcomes, relative to scenarios where there is relative certainty regarding a positive outcome but which includes the possibility of a (modest) negative outcome. Subjects seem to emphasize the relative low probability of success over the possibility of a negative outcome. The experiment provides clear indications of the pricing effect in settings where complementary units are fragmented over individual right holders. Given the stickiness of initial selling prices, and the prospective costs of the required negotiations to drive prices down to the expected value of the project, value maximizing projects might be abandoned, leading to the tragic outcome of under use or idleness. The results thus reinforce the normative hypothesis of the anticommons: property right systems should be careful in allowing the liberal creation and fragmentation of property rights

Subtyping somatic tinnitus: a cross-sectional UK cohort study of demographic, clinical and audiological characteristics

Somatic tinnitus is the ability to modulate the psychoacoustic features of tinnitus by somatic manoeuvres. The condition is still not fully understood and further identification of this subtype is essential, particularly for the purpose of establishing protocols for both its diagnosis and treatment. This study aimed to investigate the characteristics of somatic tinnitus within a large UK cohort using a largely unselected sample. We believe this to be relatively unique in comparison to current literature on the topic. This was investigated by using a total of 608 participant assessments from a set of recognised tinnitus and audiology measures. Results from a set of chi-square tests of association found that amongst the individuals with somatic tinnitus, a higher proportion had pulsatile tinnitus (different from heartbeat), were under the age of 40, reported variation in the loudness of their tinnitus and reported temporomandibular joint (TMJ) disorder. The same pattern of results was confirmed using a multivariate analysis of the data based on logistic regression. These findings have strong implications towards the profiling of somatic tinnitus as a distinct subtype of general tinnitus

Pinpointing a highly specific pathological functional connection that turns phantom sound into distress

International audienceIt has been suggested that an auditory phantom percept is the result of multiple, parallel but overlapping networks. One of those networks encodes tinnitus loudness and is electrophysiologically separable from a non-specific distress network. The present study investigates how these networks anatomically overlap, what networks are involved and how and when these networks interact. The EEG data of 317 tinnitus patients and 256 healthy subjects were analyzed, using independent component analysis. Results demonstrate that tinnitus is characterized by at least two major brain networks, each consisting of multiple independent components. One network reflects tinnitus distress, while another network reflects the loudness of the tinnitus. The component coherence analysis shows that the independent components that make up the distress and loudness networks communicate within their respective network at several discrete frequencies in parallel. The distress and loudness networks do not intercommunicate for patients without distress, but do when patients are distressed by their tinnitus. The obtained data demonstrate that the components that build up these two separable networks communicate at discrete frequencies within the network, and only between the distress and loudness networks in those patients in whom the symptoms are also clinically linked

Head-to-Head Comparison of Transcranial Random Noise Stimulation, Transcranial AC Stimulation, and Transcranial DC Stimulation for Tinnitus

Tinnitus is the perception of a sound in the absence of an external sound stimulus. This phantom sound has been related to plastic changes and hyperactivity in the auditory cortex. Different neuromodulation techniques such as transcranial magnetic stimulation and transcranial direct current stimulation (tDCS) have been used in an attempt to modify local and distant neuroplasticity as to reduce tinnitus symptoms. Recently, two techniques of pulsed electrical stimulation using weak electrical currents – transcranial alternating current stimulation (tACS) and transcranial random noise stimulation (tRNS) – have also shown significant neuromodulatory effects. In the present study we conducted the first head-to-head comparison of three different transcranial electrical stimulation (tES) techniques, namely tDCS, tACS, and tRNS in 111 tinnitus patients by placing the electrodes overlying the auditory cortex bilaterally. The results demonstrated that tRNS induced the larger transient suppressive effect on the tinnitus loudness and the tinnitus related distress as compared to tDCS and tACS. Both tDCS and tACS induced small and non-significant effects on tinnitus symptoms, supporting the superior effects of tRNS as a method for tinnitus suppression

Functional connectivity changes in adults with developmental stuttering: a preliminary study using quantitative electro-encephalography

Introduction: Stuttering is defined as speech characterized by verbal dysfluencies, but should not be seen as an isolated speech disorder, but as a generalized sensorimotor timing deficit due to impaired communication between speech related brain areas. Therefore we focused on resting state brain activity and functional connectivity. Method: We included 11 patients with developmental stuttering and 11 age matched controls. To objectify stuttering severity and the impact on quality of life (QoL), we used the Dutch validated Test for Stuttering Severity-Readers (TSS-R) and the Overall Assessment of the Speaker’s Experience of Stuttering (OASES), respectively. Furthermore, we used standardized low resolution brain electromagnetic tomography (sLORETA) analyses to look at resting state activity and functional connectivity differences and their correlations with the TSS-R and OASES. Results: No significant results could be obtained when looking at neural activity, however significant alterations in resting state functional connectivity could be demonstrated between persons who stutter (PWS) and fluently speaking controls, predominantly interhemispheric, i.e., a decreased functional connectivity for high frequency oscillations (beta and gamma) between motor speech areas (BA44 and 45) and the contralateral premotor (BA6) and motor (BA4) areas. Moreover, a positive correlation was found between functional connectivity at low frequency oscillations (theta and alpha) and stuttering severity, while a mixed increased and decreased functional connectivity at low and high frequency oscillations correlated with QoL. Discussion: PWS are characterized by decreased high frequency interhemispheric functional connectivity between motor speech, premotor and motor areas in the resting state, while higher functional connectivity in the low frequency bands indicates more severe speech disturbances, suggesting that increased interhemispheric and right sided functional connectivity is maladaptive

Whole scalp EEG power change is not a prerequisite for further EEG processing

International audienceNon