12 research outputs found
Recommended from our members
Pivotal mental states
This paper introduces a new construct, the 'pivotal mental state', which is defined as a hyper-plastic state aiding rapid and deep learning that can mediate psychological transformation. We believe this new construct bears relevance to a broad range of psychological and psychiatric phenomena. We argue that pivotal mental states serve an important evolutionary function, that is, to aid psychological transformation when actual or perceived environmental pressures demand this. We cite evidence that chronic stress and neurotic traits are primers for a pivotal mental state, whereas acute stress can be a trigger. Inspired by research with serotonin 2A receptor agonist psychedelics, we highlight how activity at this particular receptor can robustly and reliably induce pivotal mental states, but we argue that the capacity for pivotal mental states is an inherent property of the human brain itself. Moreover, we hypothesize that serotonergic psychedelics hijack a system that has evolved to mediate rapid and deep learning when its need is sensed. We cite a breadth of evidences linking stress via a variety of inducers, with an upregulated serotonin 2A receptor system (e.g. upregulated availability of and/or binding to the receptor) and acute stress with 5-HT release, which we argue can activate this primed system to induce a pivotal mental state. The pivotal mental state model is multi-level, linking a specific molecular gateway (increased serotonin 2A receptor signaling) with the inception of a hyper-plastic brain and mind state, enhanced rate of associative learning and the potential mediation of a psychological transformation
Systemic risk and food security. Emerging trends and future avenues for research
The unanticipated international food price spike of 2008 has raised concerns about global food security. Might food systems lastingly fail to supply, trade, and distribute food? Might widespread unsustainable agricultural practices irreversibly alter ecosystems? Or might large scale food shortages trigger political unrest? To answer these questions, we reflect upon the concept of systemic risk and conduct a review of the literature on systemic risks and food security. First, we present the concept of systemic risk and current trends in systemic risk research. We then analyze contributions on systemic risk and food security. We first show that the literature has so far focused on a) agricultural production and correlated yield-losses, and on ways of pooling risk at regional or global-level, and b) the role of international trade in increasing or decreasing systemic risk. We then identify avenues for further research, highlighting the impact of intensive farming on ecosystems. Finally, we discuss the concept of systemic risk: we show that scholars need to be careful when assuming that there exists just one global food system; we show that systemic risk can be understood in various ways, beyond the domino effect paradigm. © 202
Brain development in rodents and humans: Identifying benchmarks of maturation and vulnerability to injury across species
Hypoxic-ischemic and traumatic brain injuries are leading causes of long-term mortality and disability in infants and children. Although several preclinical models using rodents of different ages have been developed, species differences in the timing of key brain maturation events can render comparisons of vulnerability and regenerative capacities difficult to interpret. Traditional models of developmental brain injury have utilized rodents at postnatal day 7â10 as being roughly equivalent to a term human infant, based historically on the measurement of post-mortem brain weights during the 1970s. Here we will examine fundamental brain development processes that occur in both rodents and humans, to delineate a comparable time course of postnatal brain development across species. We consider the timing of neurogenesis, synaptogenesis, gliogenesis, oligodendrocyte maturation and age-dependent behaviors that coincide with developmentally regulated molecular and biochemical changes. In general, while the time scale is considerably different, the sequence of key events in brain maturation is largely consistent between humans and rodents. Further, there are distinct parallels in regional vulnerability as well as functional consequences in response to brain injuries. With a focus on developmental hypoxicischemic encephalopathy and traumatic brain injury, this review offers guidelines for researchers when considering the most appropriate rodent age for the developmental stage or process of interest to approximate human brain development