Empathy-related differences in the anterior cingulate functional connectivity of regular cannabis users when compared to controls.

It has been reported that cannabis consumption affects the anterior cingulate cortex (ACC), a structure with a central role in mediating the empathic response. In this study, we compared psychometric scores of empathy subscales, between a group of regular cannabis users (85, users) and a group of non-consumers (51, controls). We found that users have a greater Emotional Comprehension, a cognitive empathy trait involving the understanding of the "other" emotional state. Resting state functional MRI in a smaller sample (users = 46, controls = 34) allowed to identify greater functional connectivity (FC) of the ACC with the left somatomotor cortex (SMC), in users when compared to controls. These differences were also evident within the empathy core network, where users showed greater within network FC. The greater FC showed by the users is associated with emotional representational areas and empathy-related regions. In addition, the differences in psychometric scores suggest that users have more empathic comprehension. These findings suggest a potential association between cannabis use, a greater comprehension of the other's affective state and the functional brain organization of the users. However, further research is needed to explore such association, since many other factors may be at play.

Brain morphological variability between whites and African Americans: the importance of racial identity in brain imaging research.

In a segregated society, marked by a historical background of inequalities, there is a consistent under-representation of ethnic and racial minorities in biomedical research, causing disparities in understanding genetic and acquired diseases as well as in the effectiveness of clinical treatments affecting different groups. The repeated inclusion of small and non-representative samples of the population in neuroimaging research has led to generalization bias in the morphological characterization of the human brain. A few brain morphometric studies between Whites and African Americans have reported differences in orbitofrontal volumetry and insula cortical thickness. Nevertheless, these studies are mostly conducted in small samples and populations with cognitive impairment. For this reason, this study aimed to identify brain morphological variability due to racial identity in representative samples. We hypothesized that, in neurotypical young adults, there are differences in brain morphometry between participants with distinct racial identities. We analyzed the Human Connectome Project (HCP) database to test this hypothesis. Brain volumetry, cortical thickness, and cortical surface area measures of participants identified as Whites (n = 338) or African Americans (n = 56) were analyzed. Non-parametrical permutation analysis of covariance between these racial identity groups adjusting for age, sex, education, and economic income was implemented. Results indicated volumetric differences in choroid plexus, supratentorial, white matter, and subcortical brain structures. Moreover, differences in cortical thickness and surface area in frontal, parietal, temporal, and occipital brain regions were identified between groups. In this regard, the inclusion of sub-representative minorities in neuroimaging research, such as African American persons, is fundamental for the comprehension of human brain morphometric diversity and to design personalized clinical brain treatments for this population.

Validity of an Instrument to Detect Cheating Confirmed by the Elicited Emotional Reactions.

Cheating forms part of a complex emotional and cognitive process. However, although a relatively mundane phenomenon, instruments to evaluate cheating and its effects socially are scarce. This paper presents a five-stage approach aimed at providing validity to an instrument designed to assess cheating - specifically, its detection, and emotional reactions towards it once detected. An instrument was designed after (1) reviewing the relevant literature on cheating, in order to (2) design a bank of stimuli, (3) formulate a Delphi panel to judge the most coherent and pertinent ones, and (4) perform three pilot studies to adjust the final version of the instrument. Results from Stages 1 to 4 show that content validity was achieved for the Instrument for Detecting Cheating and its Emotional Reactions (INDETRAE, in Spanish: Instrumento para la Detección de Trampa y sus Reacciones Emocionales). Stimuli were grouped into five categories of 18 different scenarios, for a total of 90 vignettes: meaning, the INDETRAE is a 5-category, vignette-based questionnaire consisting of contrasting social cost-benefit scenarios, where the cheating situation affects an undefined, a first or a third person, and also a neutral category with no cheating. In Stage 5, several chi-squared tests (p < 0.0005) revealed significant differences between categories, proving that the instrument can indeed be used to detect cheating and to identify differentiated emotional reactions - for example, anger when there was detriment to a third person as opposed to neutral situations, or glad when there was a case of cheating which benefited the first person. The last stage counts as the first approximation to support construct validity of the INDETRAE. The most important contribution of this work consists in developing an instrument to detect cheating, confirmed by the resulting emotional reactions, which therefore demonstrate its validity.

Diverse sleep patterns, psychiatric disorders, and perceived stress in inhalants users living on the streets of Mexico City.

Homeless people face stressful circumstances influencing drug consumption, mental health, and sleep disorders. We performed an interdisciplinary study involving psychometric, polysomnographic, and ethnographic records to relate stress, psychiatric disorders, drug consumption, and sleep in ten people (four women, M = 32 y/o) living on the streets of Mexico City. Toluene-based inhalant dependence and suicidality were the more common psychiatric disorders among participants. They also presented sleep fragmentation; some manifested insomnia or sleep restriction, whereas others displayed extended rapid-eye movement sleep latencies associated with depression or inhalant consumption. Inhalants are used to improve mood, strengthen social bonds, and induce either sleep or alertness during the night. Inter-individual distinctions may be related to differential levels of intoxication, stress perception, backgrounds, and abilities to live and sleep on the street. Sleep restriction seems to be the more common factor, which may enhance the negative consequences of street situation.