Faculty Bibliography

The senses of taste and smell developed early in evolution and are of high ecological and clinical relevance in humans. Chemosensory systems function, in large part, as hazard avoidance systems, thereby ensuring survival. Moreover, they play a critical role in nutrition and in determining the flavor of foods and beverages. Their dysfunction has been shown to be a key element of early stages of a number of diseases, including Alzheimer's and Parkinson's diseases. Advanced neuroimaging methods provide a unique means for understanding, in vivo, neural and psychological processing of smell, taste, and flavor, and how diseases can impact such processing. This chapter provides, from a neuroimaging perspective, a comprehensive overview of the anatomy and physiology involved in the odor and taste processing in the central nervous system. Some methodological challenges associated with chemosensory neuroimaging research are discussed. Multisensory integration, the mechanisms that enable holistic sensory experiences, is emphasized.

Objective: To explore the applicability of an ambulatory inertial sensor (G-walk) to characterize gait function during the Timed Up and Go (TUG) Test under three different conditions.
Background(s): In Parkinson's disease (PD), the current lack of both reliable and feasible biomarkers of gait function and mobility limits the objective characterization of motor ability, clinical progression, and responsiveness to treatments. Current assessments of motor function rely on a clinicians' subjective judgement and/or the patient's self-reported questionnaires, which are not sensitive in capturing subtle changes over time and restrict comparability across raters. Ambulatory inertial sensors allow for non-invasive, wireless transmission of accurate quantitative data and therefore, may represent a useful tool in ambulatory settings. Design/Methods: Nineteen (19) PD patients (H&Y <4) and 10 agematched controls (CTRL) were consecutively enrolled to undergo inertial TUG (iTUG) testing under three experimental conditions: normal walking (iTUGnorm), dual task walking (iTUGcog), and at maximum speed (iTUGfast). The time needed to complete each test was sub-divided into six distinct phases quantified by the sensor: sitto- stand (1), forward gait (2), mid-turn (3), return gait (4), end-turn (5) and stand-to-sit (6). Other assessments included UDPRS Part III, MoCA, depression, fatigue, Benton and Rey-Osterrieth visual tests.
Result(s): A total of nineteen PD patients and ten CTRLs completed all assessments. PD patients were divided into mild (H&Y=2, n=12) and moderate (H&Y=3, n=7) disease severity. One-way-ANOVA and correlation analysis were performed. Different patterns of kinematic performance were observed (figure 1.A and 1.B). In PD, iTUG correlations were found with cognitive function, visual performance and motor severity, while in CTRLs there was only a correlation with motor performance only. iTUGfast performance seemed more sensitive experimental condition when PD was stratify by severity (figure 1.B).
Conclusion(s): iTUG assessed by an ambulatory inertial sensor is a quick, sensitive and feasible tool for objective measurements of functional mobility in PD. Utilizing validate tests for mobility and gait under different stress conditions can provide distinct information of gait function and mobility. Future longitudinal studies are warranted to better characterize the sensitivity to disease progression and the potential for monitoring and optimizing therapeutic interventions in this patient population. (Figure Presented)

Unwanted sexual incidents on university campuses pose significant public health and safety risks for students. This study explored survivors' perspectives on secondary prevention of campus sexual assault and effective strategies for intervention programs for unwanted sexual incidents in university settings. Twenty-seven student survivors of unwanted sexual experiences participated in semi-structured in-depth interviews. Data were analyzed using thematic analysis and a constructionist perspective. The findings were contextualized using the ecological model. Barriers to reporting included concerns about one's story not being believed, personal minimization of the incident, belief that no action will be taken after reporting, confidentiality concerns, and other perceived costs of reporting. Survivors provided valuable insight on potentially effective prevention and intervention strategies to address the problem of unwanted sexual incidents on university campuses. These findings may be useful for prevention and intervention policies and programs in university settings and for providers who assist survivors of unwanted sexual experiences.

The delay aversion hypothesis argues that the tendency for impulsive choice (preference for smaller sooner over larger later rewards) is motivated by the escape of negative affective states associated with delay. This model predicts that individuals with ADHD find the imposition of delay before an outcome or event especially aversive and its escape reinforcing. Consistent with this, fMRI studies show that ADHD is associated with amygdala hyper-sensitivity to cues of delay. However, evidence that delay escape is reinforcing is lacking. Here we extend fMRI research by using electrophysiological methods to study the reinforcing properties of delay-escape in ADHD. Thirty controls and 25 adolescents with ADHD aged 10-15 years performed the Escape Delay Incentive (EDI) task- in which pre-target cues indicated three conditions: i) CERTAIN DELAY: delay would follow a response irrespective of response speed ii) CONDITIONAL DELAY: delay would only follow if the response was too slow and iii) NO DELAY: delay would follow the response whatever the speed. We focused on the Contingent Negative Variation (CNV), a cue-evoked marker of motivated response preparation, across two time windows (CNV1 and CNV2). We took measures of parent, teacher and self-rated ADHD symptoms, task performance (RT) and self-rated delay aversion. We isolated CNV components and compared these between ADHD and controls. Adolescents with ADHD displayed a larger CNV2 to the CONDITIONAL DELAY than the CERTAIN DELAY cues compared to controls. However, this effect was not mirrored at the performance level and was unrelated to self-reported delay aversion. Our study provides the first ERP evidence that delay escape differentially reinforcers neural activation of attention preparation in ADHD cases. Future studies should examine the impact of varying cognitive load on task EDI performance.

OBJECTIVE:This study evaluated changes in positive affect within cognitive-behavioral treatments (CBT) for anxiety disorders. It was hypothesized that there would be significantly greater increases in positive affect in CBT conditions compared to the waitlist, and particularly higher in the Unified Protocol (UP) than the single disorder protocols (SDP) given the UP's focus on emotions (including positive emotions) rather than symptoms. METHOD:Patients with heterogeneous anxiety disorders (N = 223) were randomly assigned to the UP, SDP or waitlist. Linear mixed model regression (intent to treat) analyses were used to compare change in positive affect, quality of life, and savoring between patients in the treatment conditions (UP and SDP) versus waitlist conditions. Between condition effect sizes were calculated to assess the magnitude of difference within conditions at post-treatment. RESULTS:Results indicated a significant Group (treatment vs. waitlist) × Time (pre- post-treatment) interaction (F(1, 154.36) = 6.75; p = .01) for positive affect in which the treatment group showed significant improvements in positive affect pre- to post-treatment (ESsg = 0.37, SEsg = 0.09, 95% CI [0.20: 0.54]) and the waitlist condition did not. There were no differences between UP and SDP conditions in positive affect at baseline or at post-treatment. CONCLUSIONS:These results suggest CBT, which typically focuses on reductions in negative affect, may also improve positive affect. The importance of future research evaluating, targeting, and improving positive affect in CBT trials is discussed. Clinicaltrials.gov Identifier: NCT01243606.