Two experiments were conducted to test the prediction that rats should react with reduced sensitivity/reactivity to nociceptive stimulation in the presence of a cat. In Experiment 1, naloxone or saline was administered, and rats were exposed to no stimulus, a novel stimulus, or a cat. In Experiment 2, rats were exposed to either no stimulus or a cat, and naltrexone was administered. In both experiments, rats tested in the presence of the cat showed a significant reduction in sensitivity/reactivity to a skin-irritating formalin injection. Naltrexone reversed this analgesia.

This paper describes the results of three experiments on the global precedence effect, using stimuli derived from the receptive field characteristics of neurons in the visual cortex. Thus, the local cue consists of oriented line segments whose sizes correspond to the average size of the central portion of receptive fields in parafoveal representations of the macaque primary visual cortex. The global cue comprises these line segments distributed within larger rectangular clusters. The first experiment showed that global precedenceis obtained when the relative visibility of the localand global cues is specificallyevaluated and found to be comparable. In the second experiment, variants of the Garner sorting task produced results indicating that global processing is largely independent of localcues, but that local processing depends heavily on the status of task-irrelevant global cues. These asymmetric interactions are consistent with the notion of a priority for processing global cues. The third experiment demonstrated that the magnitude of global precedence is inversely related to pattern luminance. This latter finding is interpreted, in the context of Sternberg's additive factors logic (1969), as indicating that this priority for global feature processing is at least partially attributable to aspects of early visual processes.361

The effects of the risk of electric shock on the meal patterns of rats living in an operant chamber were investigated. Rats could obtain food by working on a response lever that provided reinforcement according to chained fixed-ratio continuous reinforcement schedules that allowed the animals control over meal size. Using a two-compartment operant chamber with a safe nesting area and manipulanda area with a grid floor, shock could be correlated with responding on the schedule. Shocks (less than or equal to 1.25 per hour) were scheduled to occur randomly throughout the day, independent of the rat's behavior. Shock caused a reorganization of meal patterns such that the animals took less frequent but larger meals. This pattern reduced the time the animals spent at risk without compromising caloric balance. Similar changes in feeding pattern were obtained in both hooded and albino rats. Exposure to shock in a separate chamber did not produce these behavioral modifications. The magnitude of shock-induced alterations of meal patterns was greater with chained fixed-ratio 90 continuous reinforcement than with chained fixed-ratio 10 continuous reinforcement. Additionally, the rats seemed to be able to reduce food intake but increase caloric efficiency, such that the reduced food intake did not have deleterious effects on maintenance of body weight. These behavioral modifications reduced the number of shocks received from that which would have been expected if meal pattern changes had not occurred. We suggest that this technique may provide a useful laboratory simulation of the impact that the risk of predation has on foraging behavior.

Telemedicine (TM) enabled by digital health technologies to provide medical services has been considered a key solution to increasing health care access in rural communities. With the immediate need for remote care due to the COVID-19 pandemic, many health care systems have rapidly incorporated digital technologies to support the delivery of remote care options, including medication treatment for individuals with opioid use disorder (OUD). In responding to the opioid crisis and the COVID-19 pandemic, public health officials and scientific communities strongly support and advocate for greater use of TM-based medication treatment for opioid use disorder (MOUD) to improve access to care and have suggested that broad use of TM during the pandemic should be sustained. Nevertheless, research on the implementation and effectiveness of TM-based MOUD has been limited. To address this knowledge gap, the National Drug Abuse Treatment Clinical Trials Network (CTN) funded (via the NIH HEAL Initiative) a study on Rural Expansion of Medication Treatment for Opioid Use Disorder (Rural MOUD; CTN-0102) to investigate the implementation and effectiveness of adding TM-based MOUD to rural primary care for expanding access to MOUD. In preparation for this large-scale, randomized controlled trial incorporating TM in rural primary care, a feasibility study is being conducted to develop and pilot test implementation procedures. In this commentary, we share some of our experiences, which include several challenges, during the initial two-month period of the feasibility study phase. While these challenges could be due, at least in part, to adjusting to the COVID-19 pandemic and new workflows to accommodate the study, they are notable and could have a substantial impact on the larger, planned pragmatic trial and on TM-based MOUD more broadly. Challenges include low rates of identification of risk for OUD from screening, low rates of referral to TM, digital device and internet access issues, workflow and capacity barriers, and insurance coverage. These challenges also highlight the lack of empirical guidance for best TM practice and quality remote care models. With TM expanding rapidly, understanding implementation and demonstrating what TM approaches are effective are critical for ensuring the best care for persons with OUD.

No abstract