Faculty Bibliography

OBJECTIVE: This study identified barriers and facilitators to the high-fidelity implementation of assertive community treatment. METHODS: As part of a multistate implementation project for evidence-based practices, training and consultation were provided to 13 newly implemented assertive community treatment teams in two states. Model fidelity was assessed at baseline and at six, 12, 18, and 24 months. Key informant interviews, surveys, and monthly on-site visits were used to monitor implementation processes related to barriers and facilitators. RESULTS: Licensing processes of the state mental health authority provided critical structural supports for implementation. These supports included a dedicated Medicaid billing structure, start-up funds, ongoing fidelity monitoring, training in the model, and technical assistance. Higher-fidelity sites had effective administrative and program leadership, low staff turnover, sound personnel practices, and skilled staff, and they allocated sufficient resources in terms of staffing, office space, and cars. Lower-fidelity sites were associated with insufficient resources, prioritization of fiscal concerns in implementation, lack of change culture, poor morale, conflict among staff, and high staff turnover. In cross-state comparisons, the specific nature of fiscal policies, licensing processes, and technical assistance appeared to influence implementation. CONCLUSIONS: State mental health authorities can play a critical role in assertive community treatment implementation but should carefully design billing mechanisms, promote technical assistance centers, link program requirements to fidelity models, and limit bureaucratic requirements. Successful implementation at the organizational level requires committed leadership, allocation of sufficient resources, and careful hiring procedures.

Standard particle filtering technique have previously been applied to the problem of fiber tracking by Brun et al. [Brun, A., Bjornemo, M., Kikinis, R., Westin, C.F., 2002. White matter tractography using sequential importance sampling. In: Proceedings of the ISMRM Annual Meeting, p. 1131] and Bjornemo et al. [Bjornemo, M., Brun, A., Kikinis, R., Westin, C.F., 2002. Regularized stochastic white matter tractography using diffusion tensor MRI, In: Proc. MICCAI, pp. 435-442]. However, these previous attempts have not utilised the full power of the technique, and as a result the fiber paths were tracked in a goal directed way. In this paper, we provide an advanced technique by presenting a fast and novel probabilistic method for white matter fiber tracking in diffusion weighted MRI (DWI), which takes advantage of the weighting and resampling mechanism of particle filtering. We formulate fiber tracking using a non-linear state space model which captures both smoothness regularity of the fibers and the uncertainties in the local fiber orientations due to noise and partial volume effects. Global fiber tracking is then posed as a problem of particle filtering. To model the posterior distribution, we classify voxels of the white matter as either prolate or oblate tensors. We then construct the orientation distributions for prolate and oblate tensors separately. Finally, the importance density function for particle filtering is modeled using the von Mises-Fisher distribution on a unit sphere. Fast and efficient sampling is achieved using Ulrich-Wood's simulation algorithm. Given a seed point, the method is able to rapidly locate the globally optimal fiber and also provides a probability map for potential connections. The proposed method is validated and compared to alternative methods both on synthetic data and real-world brain MRI datasets.

This paper examines factors associated with adherence to antiretroviral medications (ARVs) in an HIV-infected population at high risk for non-adherence: individuals living with psychiatric and substance abuse disorders. Data were examined from baseline interviews of a multisite cohort intervention study of 1138 HIV-infected adults with both a psychiatric and substance abuse disorder (based on a structured psychiatric research interview using DSM-IV criteria). The baseline interview documented mental illness and substance use in the past year, mental illness and substance abuse severity, demographics, service utilization in the past three months, general health and HIV-related conditions, self-reported spirituality and self-reported ARV medication use. Among the participants, 62% were prescribed ARVs at baseline (n = 542) and 45% of those on ARVs reported skipping medications in the past three days. Reports of non-adherence were significantly associated with having a detectable viral load (p<.01). The factors associated with non-adherence were current drug and alcohol abuse, increased psychological distress, less attendance at medical appointments, non-adherence to psychiatric medications and lower self-reported spirituality. Increased psychological distress was significantly associated with non-adherence, independent of substance abuse (p<.05). The data suggest that both mental illness and substance use must be addressed in HIV-infected adults living with these co-morbid illnesses to improve adherence to ARVs

We examined the differences in conflict interaction between depressed mothers and their toddler and non-depressed dyads and whether these differences mediated the association of maternal depression with compromised child socioemotional development. Mother/ child interaction was videotaped during a teaching task and during a free play task as part of a home visit when the target child was between 16 and 18 months old. Each turn of every conflict was coded for behavior and affect of each member of the dyad. Interaction data were summarized to calculate the number of conflict turns, the rate of conflict, and the proportion of mother-initiated versus child-initiated conflicts per dyad. Sequential analysis was used to estimate the probability of specific maternal responses to specific child behaviors. Bivariate comparisons indicated that depressed dyads experienced higher rates of conflict, especially during the teaching task, and that depressed mothers were more likely to respond destructively to child oppositional behavior. Results of multivariate linear regression indicated that the higher probability of destructive response mediated the association of maternal depression with lower quality of mother-child attachment. These findings have implications for the development of interventions to support mothers in dealing with the conflicts that are so common during the second year of a child's life.

Both odor-preference and odor-aversion learning occur in perinatal pups before the maturation of brain structures that support this learning in adults. To characterize the development of odor learning, we compared three learning paradigms: (1) odor-LiCl (0.3M; 1% body weight, ip) and (2) odor-1.2-mA shock (hindlimb, 1 sec)--both of which consistently produce odor-aversion learning throughout life and (3) odor-0.5-mA shock, which produces an odor preference in early life but an odor avoidance as pups mature. Pups were trained at postnatal day (PN) 7-8, 12-13, or 23-24, using odor-LiCl and two odor-shock conditioning paradigms of odor-0.5-mA shock and odor-1.2-mA shock. Here we show that in the youngest pups (PN7-8), odor-preference learning was associated with activity in the anterior piriform (olfactory) cortex, while odor-aversion learning was associated with activity in the posterior piriform cortex. At PN12-13, when all conditioning paradigms produced an odor aversion, the odor-0.5-mA shock, odor-1.2-mA shock, and odor-LiCl all continued producing learning-associated changes in the posterior piriform cortex. However, only odor-0.5-mA shock induced learning-associated changes within the basolateral amygdala. At weaning (PN23-24), all learning paradigms produced learning-associated changes in the posterior piriform cortex and basolateral amygdala complex. These results suggest at least two basic principles of the development of the neurobiology of learning: (1) Learning that appears similar throughout development can be supported by neural systems showing very robust developmental changes, and (2) the emergence of amygdala function depends on the learning protocol and reinforcement condition being assessed

Child maltreatment has been associated with different psychiatric disorders. Studies on both animals and humans have suggested that some brain areas would be directly affected by severe psychological trauma. The pathophysiology of post-traumatic stress disorder (PTSD) appears to be related to a complex interaction involving genetic and environmental factors. Advanced neuroimaging techniques have been used to investigate neurofunctional and neurostructural abnormalities in children, adolescents, and adults with PTSD. This review examined structural brain imaging studies that were performed in abused and traumatized children, and discusses the possible biological mechanisms involved in the pathophysiology of PTSD, the implications and future directions for magnetic resonance imaging (MRI) studies. Published reports in refereed journals were reviewed by searching Medline and examining references of the articles related to structural neuroimaging of PTSD. Structural MRI studies have been performed in adults and children to evaluate the volumetric brain alterations in the PTSD population. In contrast with studies involving adults, in which hippocampus volumetric reduction was the most consistent finding, studies involving children and adolescents with PTSD have demonstrated smaller medial and posterior portions of the corpus callosum

BACKGROUND: The Early Intervention (EI) Program of the New York City (NYC) Department of Health and Mental Hygiene provides therapeutic services to children under 3 years of age with developmental delays or disabilities. Although the EI Program targets delivery of services within 21 days of the meeting at which the Individualized Family Service Plan (IFSP) is developed, the designation of a service provider alone often takes longer than that. OBJECTIVE: This study examined associations between individual and neighborhood characteristics and timeliness of provider designation in NYC. METHODS: Multivariable logistic regression analyses were performed for 14,623 children who had their initial IFSPs developed in Fiscal Year 2004. RESULTS: Provider designation was delayed 13.4% of the time for speech therapy, 10.0% of the time for special instruction, 8.2% of the time for occupational therapy, and 4.2% of the time for physical therapy. Individual characteristics independently associated with provider designation delay were: being older than 24 months, having the IFSP meeting between July and December, having an adaptive delay, and having speech therapy or special instruction in the IFSP. Neighborhood characteristics independently associated with provider designation delay included living in a low-income neighborhood and living in a heavily Spanish-speaking neighborhood. CONCLUSION: Delayed provider designation occurs because of both individual and neighborhood factors. Interventions are needed to address shortages of providers in certain neighborhoods or with specific skills, and to address surges in administrative program functions at certain times of the year.

This study explores relationships among childhood sexual abuse (CSA), age of substance use initiation, additional traumatic events, and posttraumatic stress disorder (PTSD) in a sample of adolescents. A history of CSA that preceded substance use was not related to an earlier age of substance use initiation. Early initiation of substance use predicted exposure to additional traumatic experiences. This relationship was partially mediated by engagement in risky behavior while under the influence of substances. Posttraumatic stress disorder was related to CSA, additional traumatic experiences and engagement in risky behavior while under the influence of substances

Fear extinction, which involves learning to suppress the expression of previously learned fear, requires N-methyl-D-aspartate receptors (NMDARs) and is mediated by the amygdala and ventromedial prefrontal cortex (vmPFC). Like other types of learning, extinction involves acquisition and consolidation phases. We recently demonstrated that NR2B-containing NMDARs (NR2Bs) in the lateral amygdala (LA) are required for extinction acquisition, but whether they are involved in consolidation is not known. Further, although it has been shown that NMDARs in the vmPFC are required for extinction consolidation, whether NR2Bs in vmPFC are involved in consolidation is not known. In this report, we investigated the possible role of LA and vmPFC NR2Bs in the consolidation of fear extinction using the NR2B-selective antagonist ifenprodil. We show that systemic treatment with ifenprodil immediately after extinction training disrupts extinction consolidation. Ifenprodil infusion into vmPFC, but not the LA, immediately after extinction training also disrupts extinction consolidation. In contrast, we also show pre-extinction training infusions into vmPFC has no effect. These results, together with our previous findings showing that LA NR2Bs are required during the acquisition phase in extinction, indicate a double dissociation for the phase-dependent role of NR2Bs in the LA (acquisition, not consolidation) and vmPFC (consolidation, not acquisition)