Role of Perirhinal to Prefrontal Cortex Reciprocal Connection in Methamphetamine-Induced Memory Deficits

Chronic use of methamphetamine (meth) disrupts cortical processing across multiple cognitive domains including impulsivity, decision making and memory. Our laboratory has consistently shown that extended access to contingent meth self-administration reliably produces memory deficits in novel object recognition (NOR) tasks designed to test the “what” component of episodic memory in a rodent model. This type of memory is dependent on an intact function of the perirhinal cortex (PRH). However, the ongoing role of the prefrontal cortex (PFC) in this task and the directionality of communication between the PRH and the PFC is not entirely understood. A set of four experiments were designed to characterize the bi-directional connection between the PFC and the PRH during the exploration of novel vs. familiar objects and whether the manipulation of the circuit will restore recognition memory following chronic meth self-administration (SA). Male and female rats were infused with retrograde GFP-tagged adeno-associated virus (AAV) in the PRH (Experiment 1) and the PFC (Experiment 2). Three weeks later rats were tested for NOR with half the animals exploring two familiar objects and half exploring a novel object. Brain tissue was processed for co-labeled cells containing both GFP and c-Fos, an indicator of neuronal activation. Rats spent more time exploring novel vs. familiar objects. During novel object exploration, animals that explored novel objects had more co-labeled cells that project from the PRH to the PFC, but not in cells that project from PFC to the PRH. A dual viral approach was utilized in the second set of experiments to activate the PRH to PFC pathway following meth SA (Experiment 3) or inhibit the PRH to PFC pathway in meth naïve animals (Experiment 4). AAV viral vectors containing CRE-dependent Designer Receptors Exclusively Activated by Designer Drugs (DREADDs) were infused into the PRH while retrograde AAV encoding CRE recombinase was infused into the PFC. A recognition memory deficit was established in meth SA rats and restored through activation of excitatory DREADDS (Experiment 3). In meth naïve animals a NOR memory deficit was also induced by activation of inhibitory DREADDS within the same circuit (Experiment 4). In conclusion, this data set suggests communication from the PRH to the PFC directs novel object recognition

Permian trilobites and the applicability of the “living fossil” concept to extinct clades

Some taxa occupy our imaginations as “living fossils” because they were known from the fossil record before being discovered alive today. Other taxa are considered “living fossils” because modern relatives bear a strong morphological resemblance to fossil relatives, or because they occupy a contracted geographic range or have less diversity now than in the past, or because they represent phylogenetic diversity that requires conservation. A characterizing feature of living fossils–and thus an implicit assumption of all criteria–is that the “living fossil” of interest is extant. However, the general research questions that “living fossils” inspire–Why do rates of evolution vary across organisms, across traits, and across time? Why do some clades decline in diversity over extended periods?–may be applied to any clade, including completely extinct clades. We propose that there is nothing special about “now” when it comes to pursuing these questions and that it is unnecessarily limiting to restrict research programs to clades for which an extant member meets some conception of the “living fossil” moniker. To this end, we investigate the extent to which Permian trilobites might resemble “living fossils,” albeit from the perspective of 253 million years ago, when the last trilobites were still alive. We do so by comparing the taxonomic diversity, geographic range, and morphological disparity of trilobites living in the Permian to earlier time periods. We find that Permian trilobites meet most definitions of living fossils, although our assessment of morphological change and character retention depend on taxonomic scale

Deconstructing the Seductive Allure of Neuroscience Explanations

Previous work showed that people find explanations more satisfying when they contain irrelevant neuroscience information. The current studies investigate why this effect happens. In Study 1 (N=322), subjects judged psychology explanations that did or did not contain irrelevant neuroscience information. Longer explanations were judged more satisfying, as were explanations containing neuroscience information, but these two factors made independent contributions. In Study 2 (N=255), subjects directly compared good and bad explanations. Subjects were generally successful at selecting the good explanation except when the bad explanation contained neuroscience and the good one did not. Study 3 (N=159) tested whether neuroscience jargon was necessary for the effect, or whether it would obtain with any reference to the brain. Responses to these two conditions did not differ. These results confirm that neuroscience information exerts a seductive effect on people’s judgments, which may explain the appeal of neuroscience information within the public sphere

Comparison of Thermal Decomposition of Polystyrene Products vs. Bio-Based Polymer Aerogels

Samples of polystyrene (PS), extended polystyrene foam (EPS foam), and 3 bio-based foam-like polymer/clay aerogels were produced, and examined under pyrolysis conditions. The polystyrene products produced pyrolysis products including toluene, styrene, benzaldehyde, and 4-phenyl-1-butyne; all consistent with previous reports. These highly flammable volatiles would be further expected to combust under flame conditions, producing carbon monoxide and carbon dioxide; prior work suggests that carbon monoxide poses the greatest health risk from the burning of both polystyrene and EPS. Pectin and alginate carbohydrate polymer aerogels, subjected to the same pyrolysis conditions as the polystyrene materials, produced products which were generally consistent with prior literature, and presented only moderate known health risks (similar to those of the EPS pyrolysis). As with PS and EPS foams, the alginate and pectin aerogel by-products are flammable, and are expected to be converted to carbon oxides. Casein, a milk-derived protein, generated organic nitriles and aromatic compounds under pyrolysis conditions, again consistent with literature for proteins in general. While none of the bio-based pyrolysis products of this study pose known significant health risks, it is possible that some of nitriles could be converted to hydrogen cyanide, leading to the recommendation that such protein-based products be further investigated prior to implementation in consumer/civil engineering applications

Examining the Specificity of the Seductive Allure Effect

Previous work has found that people feel significantly moresatisfied with explanations of psychological phenomena whenthose explanations contain neuroscience information — evenwhen this information is entirely irrelevant to the logic of theexplanations. This seductive allure effect was firstdemonstrated by Weisberg, Keil, Goodstein, Rawson, & Gray(2008), and has since been replicated several times inindependent labs (e.g., Fernandez-Duque, Evans, Christian, &Hodges, 2014; Rhodes, Rodriguez, & Shah, 2014; Weisberg,Taylor, & Hopkins, 2015). However, these studies onlyexamined psychological explanations with addedneuroscience information. The current study thus investigatedthe generality of this effect and found that the seductive allureeffect occurs across several scientific disciplines wheneverthe explanations include reference to smaller components ormore fundamental processes. These data suggest that peoplehave a general preference for reductive explanations

Blood pressure and cardiac autonomic adaptations to isometric exercise training: A randomized sham‐controlled study

Isometric exercise training (IET) is increasingly cited for its role in reducing resting blood pressure (BP). Despite this, few studies have investigated a potential sham effect attributing to the success of IET, thus dictating the aim of the present study. Thirty physically inactive males (n = 15) and females (n = 15) were randomly assigned into three groups. The IET group completed a wall squat intervention at 95% peak heart rate (HR) using a prescribed knee joint angle. The sham group performed a parallel intervention, but at an intensity (<75% peak HR) previously identified to be inefficacious over a 4-week training period. No-intervention controls maintained their normal daily activities. Pre- and post-measures were taken for resting and continuous blood pressure and cardiac autonomic modulation. Resting clinic and continuous beat-to-beat systolic (−15.2 ± 9.2 and −7.3 ± 5.6 mmHg), diastolic (−4.6 ± 5 and −4.5 ± 5.1), and mean (−7 ± 4.2 and −7.5 ± 5.3) BP, respectively, all significantly decreased in the IET group compared to sham and no-intervention control. The IET group observed a significant decrease in low-frequency normalized units of heart rate variability concurrent with a significant increase in high-frequency normalized units of heart rate variability compared to both the sham and no-intervention control groups. The findings of the present study reject a nonspecific effect and further support the role of IET as an effective antihypertensive intervention. Clinical Trials ID: NCT05025202

Blood pressure and cardiac autonomic adaptations to isometric exercise training: A randomized sham-controlled study

Isometric exercise training (IET) is increasingly cited for its role in reducing resting blood pressure (BP). Despite this, few studies have investigated a potential sham effect attributing to the success of IET, thus dictating the aim of the present study. Thirty physically inactive males (n=15) and females (n=15) were randomly assigned into 3 groups. The IET group completed a wall-squat intervention at 95% peak heart rate (HR) using a prescribed knee joint angle. The sham group performed a parallel intervention, but at an intensity (<75% peak HR) previously identified to be inefficacious over a 4-week training period. No-intervention controls maintained their normal daily activities. Pre- and post-measures were taken for resting and continuous blood pressure and cardiac autonomic modulation. Resting clinic and continuous beat to beat systolic (-15.2±9.2 and -7.3±5.6 mmHg), diastolic (-4.6±5 and -4.5±5.1) and mean (-7±4.2 and -7.5±5.3) BP, respectively, all significantly decreased in the IET group compared to sham and no-intervention control. The IET group observed a significant decrease in low frequency normalised units of heart rate variability concurrent with a significant increase in high frequency normalised units of heart rate variability compared to both the sham and no-intervention control groups. The findings of the present study reject a non-specific effect and further support the role of IET as an effective anti-hypertensive intervention

Permian trilobites and the applicability of the “living fossil” concept to extinct clades

Some taxa occupy our imaginations as “living fossils” because they were known from the fossil record before being discovered alive today. Other taxa are considered “living fossils” because modern relatives bear a strong morphological resemblance to fossil relatives, or because they occupy a contracted geographic range or have less diversity now than in the past, or because they represent phylogenetic diversity that requires conservation. A characterizing feature of living fossils–and thus an implicit assumption of all criteria–is that the “living fossil” of interest is extant. However, the general research questions that “living fossils” inspire–Why do rates of evolution vary across organisms, across traits, and across time? Why do some clades decline in diversity over extended periods?–may be applied to any clade, including completely extinct clades. We propose that there is nothing special about “now” when it comes to pursuing these questions and that it is unnecessarily limiting to restrict research programs to clades for which an extant member meets some conception of the “living fossil” moniker. To this end, we investigate the extent to which Permian trilobites might resemble “living fossils,” albeit from the perspective of 253 million years ago, when the last trilobites were still alive. We do so by comparing the taxonomic diversity, geographic range, and morphological disparity of trilobites living in the Permian to earlier time periods. We find that Permian trilobites meet most definitions of living fossils, although our assessment of morphological change and character retention depend on taxonomic scale

Collateral Consequences: Living in the Shadow of a Conviction

Over the course of fifteen weeks, fourteen students and two professors explored the Criminal Justice System and the immense challenges faced by citizens as they attempt to reintegrate into their communities after being incarcerated. Through the lens of Systems Thinking, a system pioneered and described by Peter Senge, we dissected seemingly unrelated experiences to identify behaviors and patterns that have been intrinsic in the Criminal Justice System since “tough on crime” policies emerged into the early 1970’s. During this time, criminal justice and public opinion moved from a more rehabilitative stance to one of punishment and punitive vengeance on those that have wronged society, particularly those who committed drug offenses.. Along with extended sentences came a slew of collateral consequences that kept people impoverished and oppressed even after leaving prison. This specific aspect was the focus of our class’ research and discussion. By breaking this down into subsystems, the class characterized the challenges faced by citizens trying to return to their communities and normal life, and provided areas and suggestions for improving the system and in turn, the lives of these people. This book is the culmination of that research

Discovery of a Radio Relic in the Massive Merging Cluster SPT-CL 2023-5535 from the ASKAP-EMU PILOT SURVEY

The ASKAP-EMU survey is a deep wide-field radio continuum survey designed to cover the entire southern sky and a significant fraction of the northern sky up to $+30^{\circ}$. Here, we report a discovery of a radio relic in the merging cluster SPT-CL 2023-5535 at z=0.23 from the ASKAP-EMU pilot 300 sq. deg survey (800-1088 MHz). The deep high-resolution data reveal a $\sim2$ Mpc-scale radio halo elongated in the east-west direction, coincident with the intracluster gas. The radio relic is located at the western edge of this radio halo stretched $\sim0.5$ Mpc in the north-south orientation. The integrated spectral index of the radio relic within the narrow bandwidth is $\alpha^{\scriptstyle \rm 1088~MHz}_{\scriptstyle \rm 800~MHz}=-0.76 \pm 0.06$. Our weak-lensing analysis shows that the system is massive ($M_{200}=1.04\pm0.36\times 10^{15} M_{\odot}$) and composed of at least three subclusters. We suggest a scenario, wherein the radio features arise from the collision between the eastern and middle subclusters. Our discovery illustrates the effectiveness of the ASKAP-EMU survey in detecting diffuse emissions in galaxy clusters and when completed, the survey will greatly increase the number of merging cluster detections with diffuse radio emissions.Comment: Accepted to Ap