Physician Assistants/Associates With Doctoral Degrees: Where Are They Now?

PURPOSE: The impact of holding a doctoral credential by clinically practicing physician assistants/associates (PAs) remains unknown. The purpose of this study was to investigate practice patterns and describe demographic characteristics of PAs who have terminal doctoral degrees. METHODS: This was a secondary analysis of data obtained from the 2021 Salary Survey of the American Academy of PAs. A total of 13,865 PAs responded to the survey for an estimated response rate of 13.3%. We examined the relationships between holding a doctoral degree, demographic characteristics, and work-related variables. Descriptive bivariate statistics and chi-square tests were used for data analysis. RESULTS: Most of the PAs (93.6%) with doctoral degrees were older than 30 years and self-identified as female (55%). There were higher proportions of non-White individuals among those with doctorates compared with general PA population. Of the PAs holding doctoral degrees, 90.4% were primarily clinicians and 9.6% were primarily educators. Physician assistants/associates with doctoral degrees were employed with their current employer longer than PAs without doctoral degrees. Most of the PAs with doctoral degrees held informal or formal leadership and had an annual salary above the median (62.3%) compared with PAs without doctoral degrees (40.0%). CONCLUSION: There are statistically significant differences in practice patterns and demographic factors between PAs with and without doctoral degrees. Physician assistants/associates with doctoral degrees were older, were male, and held leadership positions. Taken together, holding a doctoral credential may improve upward mobility at workplaces. Qualitative studies are warranted to further understand the motivation and impact of holding a doctoral credential among clinically practicing PAs.

Impact of food insecurity and food environment on the diet quality of older African Americans during the COVID-19 pandemic.

Introduction: A high quality diet is vital in promoting wellbeing and ensuring good health, particularly for those living with chronic conditions. Older African Americans, already burdened with a higher prevalence of chronic conditions, also face a higher risk for suboptimal diets. The COVID-19 pandemic had lasting effects on access to healthy food for all Americans, but some demographic groups were disproportionately affected. Older African Americans, who already experienced reduced access to healthy food pre-pandemic, were particularly afflicted, but the full extent of the pandemic's impact on their food insecurity and food environment remains unclear. Methods: To address this gap, we conducted a study among 102 older African Americans in South Los Angeles between October 2021 and July 2022 during the COVID-19 pandemic. Participants completed surveys on dietary intake, food insecurity, and neighborhood food environment. We measured dietary quality using the healthy eating index (HEI)-2015. The analysis included descriptive, bivariate chi-square, t-tests, analysis of variance, and multiple linear and logistic regression. Results: While overall dietary quality was suboptimal, most participants met the guidelines for fruit and vegetable consumption. Food insecurity was associated with lower overall diet quality and lower total fruit and whole fruit intake. However, there was no association between food environment and diet quality. Discussion: In light of our findings, further intervention is critical to improving diet quality, especially among older African Americans living with chronic conditions in the post-pandemic era.

Impact of post-incarceration care engagement interventions on HIV transmission among young Black men who have sex with men and their sexual partners: an agent-based network modeling study.

Background: Understanding the impact of incarceration on HIV transmission among Black men who have sex with men is important given their disproportionate representation among people experiencing incarceration and the potential impact of incarceration on social and sexual networks, employment, housing, and medical care. We developed an agent-based network model (ABNM) of 10,000 agents representing young Black men who have sex with men in the city of Chicago to examine the impact of varying degrees of post-incarceration care disruption and care engagement interventions following release from jail on HIV incidence. Methods: Exponential random graph models were used to model network formation and dissolution dynamics, and network dynamics and HIV care continuum engagement were varied according to incarceration status. Hypothetical interventions to improve post-release engagement in HIV care for individuals with incarceration (e.g., enhanced case management, linkage to housing and employment services) were compared to a control scenario with no change in HIV care engagement after release. Finding: HIV incidence at 10 years was 4.98 [95% simulation interval (SI): 4.87, 5.09 per 100 person-years (py)] in the model population overall; 5.58 (95% SI 5.38, 5.76 per 100 py) among those with history of incarceration, and 12.86 (95% SI 11.89, 13.73 per 100 py) among partners of agents recently released from incarceration. Sustained post-release HIV care for agents with HIV and experiencing recent incarceration resulted in a 46% reduction in HIV incidence among post-incarceration partners [incidence rate (IR) per 100 py = 5.72 (95% SI 5.19, 6.27) vs. 10.61 (95% SI 10.09, 11.24); incidence rate ratio (IRR) = 0.54; (95% SI 0.48, 0.60)] and a 19% reduction in HIV incidence in the population overall [(IR per 100 py = 3.89 (95% SI 3.81-3.99) vs. 4.83 (95% SI 4.73, 4.92); IRR = 0.81 (95% SI 0.78, 0.83)] compared to a scenario with no change in HIV care engagement from pre-to post-release. Interpretation: Developing effective and scalable interventions to increase HIV care engagement among individuals experiencing recent incarceration and their sexual partners is needed to reduce HIV transmission among Black men who have sex with men. Funding: This work was supported by the following grants from the National Institutes of Health: R01DA039934; P20 GM 130414; P30 AI 042853; P30MH058107; T32 DA 043469; U2C DA050098 and the California HIV/AIDS Research Program: OS17-LA-003; H21PC3466.

Would the Siblings of Latinx Men Who Have Sex With Men Encourage Their Brothers to Use PrEP? Findings From a Feasibility and Acceptability Study.

We explored whether siblings can be engaged in PrEP promotion. We used the Information-Motivation-Behavior model to develop and conduct surveys and dyadic interviews with Latino men who have sex with men (LMSM) and their siblings (n = 31) and three sibling-only focus groups (n = 20). For LMSM, only n = 14 (45%) agreed they would benefit from taking PrEP, yet n = 22 (71%) would take PrEP to make their sibling worry less about them, and n = 23 (74%) requested a PrEP referral. For siblings, n = 20 (65%) believed PrEP would benefit their brother, and n = 19 (95%) in the focus groups said they would take PrEP to help their brother get started. Qualitative results include (1) siblings' support for PrEP use, (2) explicit conversations about sex were not necessary for discussing sexual health, and (3) siblings wanted to understand what they could do to encourage their brother to consider PrEP. We conclude siblings can be engaged in PrEP promotion.

Drug Use, Family Support, and Depressive Symptoms Among Latinx Sexual Minority Men: A Longitudinal Analysis.

Family rejection has negative health consequences for Latinx sexual minority men (LSMM). However, LSMM often reconcile with their families, a phenomenon cross-sectional studies miss. We analyzed longitudinal data from the Healthy Young Men's Study in Los Angeles. We used individual fixed-effects Poisson regression to model changes over time in the associations among family support, drug use, and depressive symptoms. We found that (1) the initiation of drug use was associated with a 7.2% (Ratio=1.072, 95% CI 1.006 - 1.142, p = 0.03) increase in family support among LSMM who reported high depressive symptoms (depression subscale T-score ≥ 63) in at least one data wave; (2) a 1-unit increase in family support was associated with a 4.7% (RR = ;0.953, 95% CI 0.931 - 0.976, p < 0.001) decrease in the probability of high depressive symptoms; and (3) no significant association between a change in drug use and a change in high depressive symptoms. Over time, LSMM appear to benefit from the health effects of family support associated with Latinx family structures.

Assessing Food Access, Exercise, and Dietary History among Older African American Parishioners During the COVID-19 Pandemic (C-FED Study): Design, Opportunities, Challenges, and Lessons Learned.

OBJECTIVES: Unhealthy diets and inadequate exercise are associated with chronic health conditions and excess mortality. Older African Americans do not meet dietary and exercise guidelines, and this may have worsened during the COVID-19 pandemic due to individual and environmental factors, including food insecurity. Studies evaluating these dynamics are essential for developing interventions. This narrative details a study protocol and data collection experiences during the pandemic. METHODS: Participants > 55 years African American old completed detailed food frequency, exercise, and food access questionnaires between October 2020 and July 2021. Observations of the study administrators (authors of this manuscript) for the duration of the study are presented. Details on the study design and reflections on the opportunities, challenges, and lessons learned are summarized. Future manuscripts will report data analysis of study findings. RESULTS: A total of 123 older African American adults participated in the study, and 118 (70% female) completed all three questionnaires. More than 50% of the participants had at least two primary chronic conditions. About 85% were fully vaccinated against COVID-19. Applying community-based participatory approaches, leveraging partnerships, and exercising flexibility approaches were pivotal to successfully implementing the study protocol. CONCLUSIONS: Despite challenges related to the COVID-19 pandemic, detailed data on older African American adults' diet and exercise habits were obtained. Our study design and experiences will benefit future researchers. More importantly, results from our study will inform interventions and policies aimed at minimizing consequences associated with poor diet and exercise habits during the pandemic among this vulnerable population.

Diet Quality of Older African Americans: Impact of Knowledge and Perceived Threat of COVID-19.

Confusing health messages and environmental changes intended to prevent the spread of the COVID-19 virus have affected the dietary behavior of older African Americans. We investigated the impact of COVID-19-related factors on diet quality and the relationship between food access and diet quality. We surveyed 150 African Americans aged 55 years and above during the COVID-19 pandemic. The data obtained included socio-demographic and health information, and COVID-19-related knowledge and perceptions. Dietary intake data was obtained using the Diet History Questionnaire III. Analyses included bivariate and multivariable statistics. Overall, based on United States Department of Agriculture guidelines, the diet quality of older African Americans was poor. Lower knowledge and a lower perceived threat of COVID-19 were significantly associated with poor diet quality. Additionally, older African Americans with chronic diseases and food insecurity had poor diet quality. The COVID-19 pandemic has highlighted the fragility of diet quality. The combined impact of poor knowledge and perceived threat of COVID-19, chronic disease, and food insecurity contribute to poor diet quality in this population. This study adds to the well-known need for strategies to support the right to a healthy diet, particularly during COVID-19 and future pandemics. Proactive interventions to counteract the potential consequences of poor diets are needed.

Racial/ethnic and gender disparity in the severity of NAFLD among people with diabetes or prediabetes.

Aim: Non-alcoholic fatty liver disease (NAFLD) exhibits a racial disparity. We examined the prevalence and the association between race, gender, and NAFLD among prediabetes and diabetes populations among adults in the United States. Methods: We analyzed data for 3,190 individuals ≥18 years old from the National Health and Nutrition Examination Survey (NHANES) 2017-2018. NAFLD was diagnosed by FibroScan® using controlled attenuation parameter (CAP) values: S0 (none) < 238, S1 (mild) = 238-259, S2 (moderate) = 260-290, S3 (severe) > 290. Data were analyzed using Chi-square test and multinomial logistic regression, adjusting for confounding variables and considering the design and sample weights. Results: Of the 3,190 subjects, the prevalence of NAFLD was 82.6%, 56.4%, and 30.5% (p < 0.0001) among diabetes, prediabetes and normoglycemia populations respectively. Mexican American males with prediabetes or diabetes had the highest prevalence of severe NAFLD relative to other racial/ethnic groups (p < 0.05). In the adjusted model, among the total, prediabetes, and diabetes populations, a one unit increase in HbA1c was associated with higher odds of severe NAFLD [adjusted odds ratio (AOR) = 1.8, 95% confidence level (CI) = 1.4-2.3, p < 0.0001; AOR = 2.2, 95% CI = 1.1-4.4, p = 0.033; and AOR = 1.5, 95% CI = 1.1-1.9, p = 0.003 respectively]. Conclusion: We found that prediabetes and diabetes populations had a high prevalence and higher odds of NAFLD relative to the normoglycemic population and HbA1c is an independent predictor of NAFLD severity in prediabetes and diabetes populations. Healthcare providers should screen prediabetes and diabetes populations for early detection of NAFLD and initiate treatments including lifestyle modification to prevent the progression to non-alcoholic steatohepatitis or liver cancer.

Reasons clinical education directors intend to leave their jobs.

OBJECTIVES: The goals of this study were to characterize clinical coordinators compared to other Physician Assistant (PA) faculty, and investigate factors associated with intent to leave their position, institution, and academia in the U.S. METHODS: This was a secondary analysis of data obtained from the 2019 Physician Assistant Education Association (PAEA) Faculty and Directors Survey. We examined bivariate associations with faculty role and conducted multiple logistic regression to identify predictors of intent to leave among clinical directors. RESULTS: Clinical directors indicated an intention to leave their position more often than other faculty. Factors influencing intent to leave were a lack of satisfaction with professional development and moderate to high levels of burnout. Clinical directors with severe burnout had 27x the odds of intending to leave academia. CONCLUSIONS: Our results suggest why clinical directors intend to leave and underscore the need for professional development opportunities and faculty mentoring. Faculty-centered work arrangements are needed to reduce burnout among clinical directors.

Reducing Human Immunodeficiency Virus and Sexually Transmitted Infections Risk in African American Women with At-Risk Male Partners: A Randomized Trial.

Background: We examined the efficacy of the Females of African American Legacy Empowering Self (FemAALES) intervention in a cohort of 203 publicly insured Black women in Los Angeles. Materials and Methods: Women who reported recent sex with a male partner who was at increased risk for infection by human immunodeficiency virus (HIV) and sexually transmitted infections (STI) were randomized to the six-session FemAALES intervention or to a single client-centered family planning and STI/HIV counseling session. Participants were followed at 3 and 9 months post-intervention. To investigate between-group behavioral changes in condomless sex in the prior 90 days and other HIV/STI risks, we used generalized estimating equations that accounted for repeated observations in individuals. Results: Most participants (mean age 34 ± 11 standard deviation) were low-income and unemployed, despite three-quarters having completed high school or the equivalent. The most common HIV/STI risk factors among recent male partners were incarceration (58.8%) and concurrent sex with other women (72.2%). At 3 months, the FemAALEs group showed a larger increase in the odds of asking their partner to test (adjusted odds ratio = 2.14; 95% confidence interval [CI], 1.02-4.47; p = 0.0431) and in sexual health self-efficacy scores (adjß = 1.82; 95% CI, 0.02-3.62; p = 0.0471) compared to the control group, although these changes did not hold at 9 months. Both groups showed statistically significant declines in the frequency of several sexual risk factors between baseline and 9 months. Conclusion: Although we did not find evidence that the FemAALES intervention was more efficacious than the less-intensive control condition in reducing sexual risk behaviors, the overall declines in risk behaviors we observed warrant further research. ClinicalTrials.gov (Identifier: NCT02189876).

KMT2D Deficiency Causes Sensorineural Hearing Loss in Mice and Humans.

Individuals with Kabuki syndrome type 1 (KS1) often have hearing loss recognized in middle childhood. Current clinical dogma suggests that this phenotype is caused by frequent infections due to the immune deficiency in KS1 and/or secondary to structural abnormalities of the ear. To clarify some aspects of hearing loss, we collected information on hearing status from 21 individuals with KS1 and found that individuals have both sensorineural and conductive hearing loss, with the average age of presentation being 7 years. Our data suggest that while ear infections and structural abnormalities contribute to the observed hearing loss, these factors do not explain all loss. Using a KS1 mouse model, we found hearing abnormalities from hearing onset, as indicated by auditory brainstem response measurements. In contrast to mouse and human data for CHARGE syndrome, a disorder possessing overlapping clinical features with KS and a well-known cause of hearing loss and structural inner ear abnormalities, there are no apparent structural abnormalities of the cochlea in KS1 mice. The KS1 mice also display diminished distortion product otoacoustic emission levels, which suggests outer hair cell dysfunction. Combining these findings, our data suggests that KMT2D dysfunction causes sensorineural hearing loss compounded with external factors, such as infection.

Sources of variability in auditory brainstem response thresholds in a mouse model of noise-induced hearing loss.

Numerous and non-acoustic experimental factors can potentially influence experimental outcomes in animal models when measuring the effects of noise exposures. Subject-related factors, including species, strain, age, sex, body weight, and post-exposure measurement timepoints, influence the observed hearing deficits. Experimenter effects, such as experience with experimental techniques and animal handling, may also factor into reported thresholds. In this study, the influence of subject sex, body mass, age at noise exposure, and timepoint of post-exposure recording are reported from a large sample of CBA/CaJ mice. Auditory brainstem response (ABR) thresholds differed between noise-exposed and unexposed mice, although the differences varied across tone frequencies. Thresholds across age at noise exposures and measurement delays after exposure also differed for some timepoints. Higher body mass correlated with higher ABR thresholds for unexposed male and female mice, but not for noise-exposed mice. Together, these factors may contribute to differences in phenotypic outcomes observed across studies or even within a single laboratory.

Academic leadership in physician assistant/associate medical education: a cross-sectional analysis of the association with doctoral degree, gender, and minority status.

BACKGROUND: There is a critical need for a diverse pool of academic leaders to increase the number and diversity of the medical workforce. Physician Assistant/Associate (PA) is a growing medical profession. Although the master's degree is the terminal degree for PAs, a growing number of PAs obtain a variety of doctoral degrees. However, there is no standardized training for academic PA leaders. The purpose of this study was to identify factors associated with PA academic leadership. Specifically, this study explored the following factors: doctoral degree credentials, gender and underrepresented minority status. METHODS: Using the 2019 Physician Assistant Education Association Faculty and Directors survey, we assessed the relationship between academic leadership groups [Program Director (PD), Academic Director (AD), and Clinical Director (CD)] doctoral degree, gender, and underrepresented minority in medicine (URIM) status. Multivariable logistic regression models were used to determine the predictors of being in a leadership role. Results with p < 0.05 were considered statistically significant. RESULTS: Of the 956 participants, 71% were female, 4% Hispanic, 86% White, 4% Black, 2% Asian, and 1% Native Hawaiian/Pacific Islander/American Indian/Alaska Native. Overall, 9% were URIM. Mean age was 45.6 (SD = 10.2) years. Average time in PA education was 2.9 years (SD = 1.4). Approximately 50% (n = 472) had a leadership role (PD-24%, AD-10%, CD-16%). Of all leaders, 68% were female, 9% were URIM, and 19% had a doctoral degree. Having a doctoral degree increased the odds of being a PD [AOR 2.38, CI [1.57-3.59], p = < 0.0001, AD and CD = non-significant]. More time in PA education increased the odds of being a PD [AOR 1.10, CI [1.07-1.12, p = < 0.0001] and AD [AOR 1.06, CI [1.03-1.09], p = < 0.0001], but not a CD. Gender and URIM status were not significantly associated with leadership roles. URIMs had doctorate degrees at higher rates than non-URIMs. CONCLUSION: PA academic leaders differ by doctoral degree attainment but not by gender and URIM status. URIM faculty are grossly underrepresented in the PA professorate, but disproportionately have doctoral degrees. Academic training opportunities for all PA academic leaders and strategies to increase URIM faculty are needed.

An exploratory study to characterize the HIV testing-to-care continuum to improve outcomes for Black and Latinx residents of South Los Angeles.

BACKGROUND: South Los Angeles (SPA6), with mostly Black (27.4%) and Latinx (68.2%) residents, has the second highest rates of new HIV diagnoses (31 per 100,000) in Los Angeles County. However, there is limited understanding of the HIV testing-to-care continuum among newly diagnosed in this setting. METHODS: We conducted an exploratory study that analyzed de-identified data, including demographic characteristics and biomedical outcomes, from the electronic medical records of individuals newly diagnosed with HIV from 2016-2020 at the only public safety-net, county-run health department HIV clinic in SPA 6. We used Pearson Chi-square and Fisher's Exact test to explore associations with HIV outcomes and a Kaplan-Meier survival curve to assess the time to linkage to care. RESULTS: A total of 281 patients were identified. The majority (74.1%) presented with a baseline CD4 <500, many of which presented with a CD4<200 (39.2%). We found twice as many newly diagnosed Black individuals in our study population (48.2%) when compared to LAC (23%), despite only accounting for 27.4% of residents in SPA 6. The majority were linked to care within 30 days of positive test and prescribed anti-retroviral therapy. Viral suppression (59.8%) and undetectable VL (52.6%) were achieved within the year following diagnosis, with 9.3% lost to follow-up. Of those who became virally suppressed, 20.7% experienced viral rebound within the year following diagnosis. CONCLUSION: The large proportion of patients with a baseline CD4 <500 raises concerns about late diagnoses. Despite high rates of linkage to care and ART prescription, achievement of sustained viral suppression remains low with high rates of viral rebound. Longitudinal studies are needed to understand the barriers to early testing, retention in care, and treatment adherence to develop strategies and interventions with community organizations that respond to the unique needs of people living with HIV in South Los Angeles.

Effects of Noise Exposure and Aging on Behavioral Tone Detection in Quiet and Noise by Mice.

Aging leads to degeneration of the peripheral and central auditory systems, hearing loss, and difficulty understanding sounds in noise. Aging is also associated with changes in susceptibility to or recovery from damaging noise exposures, although the effects of the interaction between acute noise exposure and age on the perception of sounds are not well studied. We tested these effects in the CBA/CaJ mouse model of age-related hearing loss using operant conditioning procedures before and after noise exposure and longitudinally measured changes in their sensitivity for detecting tones in quiet or noise backgrounds. Cochleae from a subset of the behaviorally tested mice were immunolabeled to examine organ of Corti damage relative to what is expected based on aging alone. Mice tested in both quiet and noise background conditions experienced worse behavioral sensitivity immediately after noise exposure, but mice exposed at older ages generally showed greater threshold shifts and reduced recovery over time. Surprisingly, day-to-day stability in thresholds was markedly higher for mice detecting signals in the presence of a noise masker compared with detection in quiet conditions. Cochlear analysis revealed decreases in the total number of outer hair cells (OHCs) and the number of ribbons per inner cell in high-frequency regions in aged, noise-exposed mice relative to aging alone. Our findings build on previous work showing interactions between age and noise exposure and add that background noise can increase the stability of behavioral hearing sensitivity after noise damage.

Minority Stress and Sexual Functioning Among African American Women With At-Risk Partners in South Los Angeles.

BACKGROUND: Preliminary evidence indicates that acute and chronic psychological stress affect sexual arousal and satisfaction. African American women, in particular, are vulnerable to the impacts of gender- and race-related stress, given their socially constructed identities as African Americans and as women. AIM: We examined associations between minority stress and sexual function using data from 248 African American women. METHODS: Surveys were conducted with 248 African American women in South LA with male partners at risk for acquiring HIV. We analyzed self-reports on (i) stress indicators: chronic burden, perceived racism/sexism, and histories of trauma/sexual abuse; (ii) Female Sexual Function Index domains: desire, arousal, and satisfaction; and (iii) potential moderators: social support and spirituality. We used multiple regression, adjusting for potential confounding factors, to examine the relationships between stress indictors, potential moderators, and sexual function domains. OUTCOMES: The outcomes were the female sexual function index domains of desire, arousal, and satisfaction. RESULTS: This largely low-income sample experienced significant chronic and acute stressors, was highly spiritual and reported strong social support. Moderate-high chronic burden and increasing sexism scores were independently associated with decreased arousal (B = -0.38, 95%CI = -0.75, -0.02) and satisfaction (B = -0.03, 95%CI = -0.06, 0.00) scores, respectively. CLINICAL IMPLICATIONS: Providers may want to explore chronic burden in patients who complain about low sexual arousal. Additionally, to develop effective HIV- and other STI-related interventions that impact behaviors that can confer sexual risk, prevention strategies are needed that either reduce contextual stressors or mitigate their impact. STRENGTHS: Strengths of this research are that it focuses on sexual function among previously under-studied, low-income African American women and that it takes into account the unique set of stressors faced by these women. LIMITATIONS: A limitation is that the sample size may have been too small to capture the effects of potential moderators. CONCLUSIONS: Low-income African American women accumulate life stressors that may harm sexual function. Schrode K, Poareo E, Li M, et al. Minority Stress and Sexual Functioning Among African American Women With At-Risk Partners in South Los Angeles. J Sex Med 2022;19:603-612.

Factors predicting incarceration history and incidence among Black and Latino men who have sex with men (MSM) residing in a major urban center.

We analyzed data from a cohort of Black and Latino men who have sex with men (MSM) in order to identify correlates of prevalent and incident incarceration, including potential predictors related to their status as sexual and gender minorities (SGMs). Baseline and follow-up self-administered survey data were examined from Los Angeles County participants' ages 18-45 years at enrollment who were either HIV negative or living with HIV, but recruited to over represent men who used drugs and men with unsuppressed HIV infection. Multivariable logistic regression models were developed to identify predictors of baseline incarceration history and of incident incarceration over study follow-up among 440 and 338 participants, respectively. Older age, Black race, low socioeconomic status, homelessness, stimulant use, and depression symptoms were associated with baseline incarceration history. The only SGM-related factor associated with baseline incarceration history was having experienced violence based on sexual orientation identity. Just one statistically significant, independent positive predictor of incident incarceration was identified: prior incarceration, whereas having four or more friends that could lend money was a statistically significant protective factor against incident incarceration. Fundamental Cause Theory provides a useful framework to explain identified predictors of incarceration. Addressing poverty, housing instability, inadequate access to health care, and their root causes is critical to reducing incarceration rates in this population, as is expanded access to both diversion and anti-recidivism programs and to evidence-based treatment for stimulant use disorders.

Auditory Behavior in Adult-Blinded Mice.

Cross-modal plasticity occurs when the function of remaining senses is enhanced following deprivation or loss of a sensory modality. Auditory neural responses are enhanced in the auditory cortex, including increased sensitivity and frequency selectivity, following short-term visual deprivation in adult mice (Petrus et al. Neuron 81:664-673, 2014). Whether or not these visual deprivation-induced neural changes translate into improved auditory perception and performance remains unclear. As an initial investigation of the effects of adult visual deprivation on auditory behaviors, CBA/CaJ mice underwent binocular enucleation at 3-4 weeks old and were tested on a battery of learned behavioral tasks, acoustic startle response (ASR), and prepulse inhibition (PPI) tests beginning at least 2 weeks after the enucleation procedure. Auditory brain stem responses (ABRs) were also measured to screen for potential effects of visual deprivation on non-behavioral hearing function. Control and enucleated mice showed similar tone detection sensitivity and frequency discrimination in a conditioned lick suppression test. Both groups showed normal reactivity to sound as measured by ASR in a quiet background. However, when startle-eliciting stimuli were presented in noise, enucleated mice showed decreased ASR amplitude relative to controls. Control and enucleated mice displayed no significant differences in ASR habituation, PPI tests, or ABR thresholds, or wave morphology. Our findings suggest that while adult-onset visual deprivation induces cross-modal plasticity at the synaptic and circuit levels, it does not substantially influence simple auditory behavioral performance.