Prefrontal Cortex Based Sex Differences in Tinnitus Perception: Same Tinnitus Intensity, Same Tinnitus Distress, Different Mood

BACKGROUND: Tinnitus refers to auditory phantom sensation. It is estimated that for 2% of the population this auditory phantom percept severely affects the quality of life, due to tinnitus related distress. Although the overall distress levels do not differ between sexes in tinnitus, females are more influenced by distress than males. Typically, pain, sleep, and depression are perceived as significantly more severe by female tinnitus patients. Studies on gender differences in emotional regulation indicate that females with high depressive symptoms show greater attention to emotion, and use less anti-rumination emotional repair strategies than males. METHODOLOGY: The objective of this study was to verify whether the activity and connectivity of the resting brain is different for male and female tinnitus patients using resting-state EEG. CONCLUSIONS: Females had a higher mean score than male tinnitus patients on the BDI-II. Female tinnitus patients differ from male tinnitus patients in the orbitofrontal cortex (OFC) extending to the frontopolar cortex in beta1 and beta2. The OFC is important for emotional processing of sounds. Increased functional alpha connectivity is found between the OFC, insula, subgenual anterior cingulate (sgACC), parahippocampal (PHC) areas and the auditory cortex in females. Our data suggest increased functional connectivity that binds tinnitus-related auditory cortex activity to auditory emotion-related areas via the PHC-sgACC connections resulting in a more depressive state even though the tinnitus intensity and tinnitus-related distress are not different from men. Comparing male tinnitus patients to a control group of males significant differences could be found for beta3 in the posterior cingulate cortex (PCC). The PCC might be related to cognitive and memory-related aspects of the tinnitus percept. Our results propose that sex influences in tinnitus research cannot be ignored and should be taken into account in functional imaging studies related to tinnitus

Nitrous Oxide Inhalation Among Adolescents: Prevalence, Correlates, and Co-Occurrence with Volatile Solvent Inhalation

Few studies have examined the prevalence of nitrous oxide (NO) inhalation or co-occurrence of NO and volatile solvent (VS) use in adolescents. Study aims were to (1) describe the independent and conjoint prevalence of NO and VS use in incarcerated youth, (2) compare adolescent users of both NO and VS inhalants (NO+VS) to users of NO-only, VS-only, and nonusers of NO and VS (NO/VNS nonusers) with regard to demographic, psychological, and behavioral characteristics, and (3) conduct logistic regression analyses identifying correlates of NO use. Residents (N = 723) of Missouri Division of Youth Services were assessed with standardized psychosocial measures. Participants averaged 15.5 (SD = 1.2) years of age, were ethnically diverse and predominantly male. Lifetime prevalence of NO use was 15.8%. NO+VS users evidenced greater impairments compared to NO+VS nonusers. VS-only users evidenced impairments that were similar in kind but at lower prevalences compared to those displayed by NO+VS users, whereas NO-only youth had profiles that were similar to those of NO/VS nonusers. Psychiatric disorders, polydrug use, and temperamental fearlessness were correlates of NO use. NO+VS users were at high risk for behavioral and emotional problems. Screening and interventions for NO and VS inhalant use should be implemented in juvenile justice facilities.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/78160/1/nihms217666.pd

Investigating Functional Cooperation in the Human Brain Using Simple Graph-Theoretic Methods

This paper introduces a very simple analytic method for mining large numbers of brain imaging experiments to discover functional cooperation between regions. We then report some preliminary results of its application, illustrate some of the many future projects in which we expect the technique will be of considerable use (including a way to relate fMRI to EEG), and describe a research resource for investigating functional cooperation in the cortex that will be made publicly available through the lab website. One significant finding is that differences between cognitive domains appear to be attributable more to differences in patterns of cooperation between brain regions, rather than to differences in which brain regions are used in each domain. This is not a result that is predicted by prevailing localization‐based and modular accounts of the organization of the cortex. Introduction and Background Hardly an issue of Science or Nature goes by without creating a stir over the discovery of “the” gene for some disease, trait, or predisposition, or “the ” brain area responsible for some behavior or cognitive capacity. Of course, we know better; the isolable parts of complex systems like th