No abstract

The purpose of the present study was to establish a short paradigm for the examination of classical aversive conditioning processes for application in patients with anxiety disorders. We measured behavioral, autonomic and neural correlates of the paradigm in healthy subjects, applying functional magnetic resonance imaging (fMRI) and measurement of skin conductance. Therefore, neutral visual stimuli were paired with an unpleasant white noise as unconditioned stimulus. Twenty healthy subjects performed three experimental phases of learning: familiarization, acquisition and extinction. Subjective ratings of valence and arousal after each phase of conditioning as well as skin conductance measurement indicated successful conditioning. During acquisition, fMRI results showed increased activation for the conditioned stimulus (CS+(unpaired)) when compared with the non-conditioned stimulus (CS-) in the right amygdala, the insulae, the anterior cingulate cortex and the parahippocampal gyrus, all regions known to be involved in emotional processing. In addition, a linearly decreasing activation in the right amygdala/hippocampus for the CS- across the acquisition phase was found. There were no significant differences between CS+ and CS- during extinction. In conclusion, the applicability of this paradigm for the evaluation of neural correlates in conditioning and extinction processes has been proven. Thus, we present a promising paradigm for the examination of the fear-circuit in patients with anxiety disorders and additionally effects of cognitive-behavioral interventions.

The brain structural changes related to gender incongruence (GI) are still poorly understood. Previous studies comparing gray matter volumes (GMV) between cisgender and transgender individuals with GI revealed conflicting results. Leveraging a comprehensive sample of transmen (n = 33), transwomen (n = 33), cismen (n = 24), and ciswomen (n = 25), we employ a region-of-interest (ROI) approach to examine the most frequently reported brain regions showing GMV differences between trans- and cisgender individuals. The primary aim is to replicate previous findings and identify anatomical regions which differ between transgender individuals with GI and cisgender individuals. On the basis of a comprehensive literature search, we selected a set of ROIs (thalamus, putamen, cerebellum, angular gyrus, precentral gyrus) for which differences between cis- and transgender groups have been previously observed. The putamen was the only region showing significant GMV differences between cis- and transgender, across previous studies and the present study. We observed increased GMV in the putamen for transwomen compared to both transmen and ciswomen and for all transgender participants compared to all cisgender participants. Such a pattern of neuroanatomical differences corroborates the large majority of previous studies. This potential replication of previous findings and the known involvement of the putamen in cognitive processes related to body representations and the creation of the own body image indicate the relevance of this region for GI and its potential as a structural biomarker for GI.

Robots are ever more relevant for everyday life, such as healthcare or rehabilitation, as well as for modern industrial environment. One important issue in this context is the way we perceive robots and their actions. From our previous study, evidence exists that sex can affect the way people perceive certain robot's actions. In our fMRI study, we analyzed brain activations of female and male participants, while they observed anthropomorphic and robotic movements performed by a human or a robot model. While lying in the scanner, participants rated the perceived level of anthropomorphic and robotic likeness of movements in the two models. The observation of the human model and the anthropomorphic movements similarly activated the biological motion coding areas in posterior temporal and parietal areas. The observation of the robot model activated predominantly areas of the ventral stream, whereas the observation of robotic movements activated predominantly the primary and higher order motor areas. To note, this later activation originated mainly from female participants, whereas male participants activated, in both robot model and robotic movements contrasts, areas in the posterior parietal cortex. Accordingly, the general contrast of sex suggests that men tend to use the ventro-dorsal stream most plausibly to rely on available previous knowledge to analyze the movements, whereas female participants use the dorso-dorsal and the ventral streams to analyze online the differences between the movement types and between the different models. The study is a first step toward the understanding of sex differences in the processing of anthropomorphic and robotic movements.