Biological aging of two innate behaviors of Drosophila melanogaster: Escape climbing versus courtship learning and memory.

Motor and cognitive aging can severely affect life quality of elderly people and burden health care systems. In search for diagnostic behavioral biomarkers, it has been suggested that walking speed can predict forms of cognitive decline, but in humans, it remains challenging to separate the effects of biological aging and lifestyle. We examined a possible association of motor and cognitive decline in Drosophila, a genetic model organism of healthy aging. Long term courtship memory is present in young male flies but absent already during mid life (4-8 weeks). By contrast, courtship learning index and short term memory (STM) are surprisingly robust and remain stable through mid (4-8 weeks) and healthy late life (>8 weeks), until courtship performance collapses suddenly at ~4.5 days prior to death. By contrast, climbing speed declines gradually during late life (>8 weeks). The collapse of courtship performance and short term memory close to the end of life occur later and progress with a different time course than the gradual late life decline in climbing speed. Thus, during healthy aging in male Drosophila, climbing and courtship motor behaviors decline differentially. Moreover, cognitive and motor performances decline at different time courses. Differential behavioral decline during aging may indicate different underlying causes, or alternatively, a common cause but different thresholds for defects in different behaviors.

[Research progress on the neural mechanism of the regulation of social isolation on innate behaviors].

Innate behavior is mainly controlled by genetics, but is also regulated by social experiences such as social isolation. Studies in animal models such as Drosophila and mice have found that social isolation can regulate innate behaviors through the changes at the molecular level, such as hormone, neurotransmitter, neuropeptide level, and at the level of neural circuits. In this review, we summarized the research progress on the regulation of social isolation on various animal innate behaviors, such as sleep, reproduction and aggression by altering the expression of conserved neuropeptides and neurotransmitters, hoping to deepen the understanding of the key and conserved signal pathways that regulate innate behavior by social isolation.

Gut instincts: Unveiling the connection between gut microbiota and Alzheimer's disease.

Alzheimer's disease (AD) is a neurodegenerative disorder marked by neuroinflammation and gradual cognitive decline. Recent research has revealed that the gut microbiota (GM) plays an important role in the pathogenesis of AD through the microbiota-gut-brain axis. However, the mechanism by which GM and microbial metabolites alter brain function is not clearly understood. GM dysbiosis increases the permeability of the intestine, alters the blood-brain barrier permeability, and elevates proinflammatory mediators causing neurodegeneration. This review article introduced us to the composition and functions of GM along with its repercussions of dysbiosis in relation to AD. We also discussed the importance of the gut-brain axis and its role in communication. Later we focused on the mechanism behind gut dysbiosis and the progression of AD including neuroinflammation, oxidative stress, and changes in neurotransmitter levels. Furthermore, we highlighted recent developments in AD management, such as microbiota-based therapy, dietary interventions like prebiotics, probiotics, and fecal microbiota transplantation. Finally, we concluded with challenges and future directions in AD research based on GM.

Is food preference innate instinct driven or human's free will?

The question whether food preference decisions are controlled by innate instincts, or a conscious decision-making process is still open. The answer to this question is important not only for neuroscientists, psychologists, and philosophers but also for food scientists and developers. Looking from different perspectives involved in food preference decisions could not only settle a long ongoing debate but also pave the way to understand why people prefer to eat what they eat.

The forgotten militant and his enduring mission: Zing-Yang Kuo and his extraordinary years in behavioral neuroembryology (1929-1939).

Zing-Yang Kuo (1898-1970), hailed as China's behaviorist psychologist, earned "Out-Watsons Mr. Watson" in the international anti-instinct movement. His contributions to the field on behavioral neuroembryology (1929-1939) are often overlooked in comparison to his achievements in psychology. We retrieved the titles of all of Kuo's publications from 1929 to 1939 and examined those related to his research on the origins and development of embryonic behavioral ontogeny and the neural basis of embryonic behavior. Remarkably, Kuo concurrently focused on embryos during the same period as North American neuroembryologists. He maintained an independent stance in the debate over the sequence of behavioral ontogeny, represented by the embryonic neuroscientists Coghill and Windle, and critically pointed out limitations in research on both sides of the debate. Drawing from his experiments with chicken embryos, Kuo proposed the theory of behavioral epigenesis, which attempted to end the nature-nurture dichotomy and promote the transformation of the research path of behavioral embryology from elementary physiological anatomy toward a deep "comprehensive science." Kuo's achievements directly laid the foundation for the interdisciplinary field of developmental psychobiology, constructing a new conceptual framework for the systematic analysis of behavioral development and promoting the establishment and development of a new approach to epiphenotype epigenetics.

Killer instincts: natural killer cells as multifactorial cancer immunotherapy.

Natural killer (NK) cells integrate heterogeneous signals for activation and inhibition using germline-encoded receptors. These receptors are stochastically co-expressed, and their concurrent engagement and signaling can adjust the sensitivity of individual cells to putative targets. Against cancers, which mutate and evolve under therapeutic and immunologic pressure, the diversity for recognition provided by NK cells may be key to comprehensive cancer control. NK cells are already being trialled as adoptive cell therapy and targets for immunotherapeutic agents. However, strategies to leverage their naturally occurring diversity and agility have not yet been developed. In this review, we discuss the receptors and signaling pathways through which signals for activation or inhibition are generated in NK cells, focusing on their roles in cancer and potential as targets for immunotherapies. Finally, we consider the impacts of receptor co-expression and the potential to engage multiple pathways of NK cell reactivity to maximize the scope and strength of antitumor activities.

A direction-selective cortico-brainstem pathway adaptively modulates innate behaviors.

Sensory cortices modulate innate behaviors through corticofugal projections targeting phylogenetically-old brainstem nuclei. However, the principles behind the functional connectivity of these projections remain poorly understood. Here, we show that in mice visual cortical neurons projecting to the optic-tract and dorsal-terminal nuclei (NOT-DTN) possess distinct response properties and anatomical connectivity, supporting the adaption of an essential innate eye movement, the optokinetic reflex (OKR). We find that these corticofugal neurons are enriched in specific visual areas, and they prefer temporo-nasal visual motion, matching the direction bias of downstream NOT-DTN neurons. Remarkably, continuous OKR stimulation selectively enhances the activity of these temporo-nasally biased cortical neurons, which can efficiently promote OKR plasticity. Lastly, we demonstrate that silencing downstream NOT-DTN neurons, which project specifically to the inferior olive-a key structure in oculomotor plasticity, impairs the cortical modulation of OKR and OKR plasticity. Our results unveil a direction-selective cortico-brainstem pathway that adaptively modulates innate behaviors.

The Ego and the Id: Concepts and developments.

In this note I have limited myself to describing some convergent and divergent developments arising from the innovative concepts present in The Ego and the Id. It could be argued that a part of the psychoanalytic movement wished to emphasize the function of the Ego (Anna Freud, Hartmann, Rapaport), while another part (Melanie Klein and her followers) delved into the dynamics of the Superego and the Id in primitive and pathological states of mind. I will examine three themes presents in The Ego and the Id: the assertion that a part of the Ego is unconscious; the idea that the death drive becomes part of the dynamics of melancholia and its Superego; the concept of fusion and defusion of the life and death instinct. Freud's writing represents a forge of new ideas that have made psychoanalysis ever more creative and capable of understanding the complexity and mysteriousness of the human mind.

Passivity and Gender: Psychical inertia and maternal stillness.

Who is afraid of passivity? Historically, women and minoritized people have had good reason to be, given that passivity has been a way to keep them out of the world of "reason." Freud's move from the activity/passivity binary as the principle of all instinct, to its gendering as femininity/passivity and masculinity/activity, leads him to assert the "repudiation of femininity" as the bedrock of psychic life (Freud, S. 1937. "Analysis Terminable and Interminable." In The Standard Edition of the Complete Psychological Works of Sigmund Freud, 23, 209-254. London: Hogarth Press). This has led to a generative history of feminist, queer and Black psychoanalytic scholarship that constantly re-opens the question of female subjectivity and sexuality, and what we mean by psychic femininity and masculinity. However, what does remains as "bedrock," even in this theorizing, is the figure of the mother in the internal world of the infant - supposedly castrated yet all-powerful, and requiring that the infant defend itself against what is stirred up as a result of dependency on her. After reviewing some of the psychoanalytic debates about femininity, I turn to "stillness" rather than passivity to suggest that we can identify a maternal element that is on the side of development, a figuration of psychical inertia that holds the capacity for waiting, stopping, ceasing and withdrawing in a world in which these mental functions are sorely missing.

Cell assembly analysis of neural circuits for innate behavior in Drosophila melanogaster using an immediate early gene stripe/egr-1.

Innate behavior, such as courtship behavior, is controlled by a genetically defined set of neurons. To date, it remains challenging to visualize and artificially control the neural population that is active during innate behavior in a whole-brain scale. Immediate early genes (IEGs), whose expression is induced by neural activity, can serve as powerful tools to map neural activity in the animal brain. We screened for IEGs in vinegar fly Drosophila melanogaster and identified stripe/egr-1 as a potent neural activity marker. Focusing on male courtship as a model of innate behavior, we demonstrate that stripe-GAL4-mediated reporter expression can label fruitless (fru)-expressing neurons involved in courtship in an activity (experience)-dependent manner. Optogenetic reactivation of the labeled neurons elicited sexual behavior in males, whereas silencing of the labeled neurons suppressed courtship and copulation. Further, by combining stripe-GAL4-mediated reporter expression and detection of endogenous Stripe expression, we established methods that can label neurons activated under different contexts in separate time windows in the same animal. The cell assembly analysis of fru neural population in males revealed that distinct groups of neurons are activated during interactions with a female or another male. These methods will contribute to building a deeper understanding of neural circuit mechanisms underlying innate insect behavior.

Gut instinct: Sex differences in the gut microbiome are associated with changes in adolescent nociception following maternal separation in rats.

Adolescent chronic pain is a growing public health epidemic. Our understanding of its etiology is limited; however, several factors can increase susceptibility, often developing in response to an acute pain trigger such as a surgical procedure or mild traumatic brain injury (mTBI), or an adverse childhood experience (ACE). Additionally, the prevalence and manifestation of chronic pain is sexually dimorphic, with double the rates in females than males. Despite this, the majority of pre-clinical pain research focuses on males, leaving a gap in mechanistic understanding for females. Given that emerging evidence has linked the gut microbiome and the brain-gut-immune axis to various pain disorders, we aimed to investigate sex-dependent changes in taxonomic and functional gut microbiome features following an ACE and acute injury as chronic pain triggers. Male and female Sprague Dawley rat pups were randomly assigned to either a maternal separation (MS) or no stress paradigm, then further into a sham, mTBI, or surgery condition. Chronically, the von Frey test was used to measure mechanical nociception, and fecal samples were collected for 16S rRNA sequencing. Animals in the surgery group had an increase in pain sensitivity when compared to mTBI and sham groups, and this was complemented by changes to the gut microbiome. In addition, significant sex differences were identified in gut microbiome composition, which were exacerbated in response to MS. Overall, we provide preliminary evidence for sex differences and ACE-induced changes in bacterial composition that, when combined, may be contributing to heterogeneity in pain outcomes.

First record of geophagy in Jungle Babbler (Turdoides striata) prior to egg-laying: an instinct for calcium supplement.

Geophagy has been documented in different animal taxa including Aves and particularly in Passeriformes. However, no geophagic activity has been reported in the genus Turdoides of the family Leiothrichidae belonging to the passerine order. Studies reveal the behaviour of geophagy to be aiding in nutrient supplementation, toxin neutralisation, cytoprotection, gut pH stabilisation and parasite liberation. Here, we provide a record of geophagy in Jungle Babbler Turdoides striata in a peri-urban area of Berhampur city in India. Although this species, being insectivorous, was thought to be feeding on insects, nevertheless, close observations confirmed the activity to be a case of geophagy, which was followed up by nest-building, egg-laying and hatching. The soil samples from the geophagic sites (Ca = 2415 mg/kg) contained 130% more Ca than that of the non-geophagic sites (Ca = 1050 mg/kg). The biochemical requirement of calcium throughout the reproductive phase of Turdoides sp. may corroborate the soil consumption instinct, which was also extrapolated from the reproductive success observed, because the demand for calcium in birds remains high during the egg-laying time. Although the possible explanations for geophagy, reported for the first time in this species, were oriented specifically towards Ca supplement, the present findings provide impetus for furthering research in this domain.

An 'instinct for learning': the learning flights and walks of bees, wasps and ants from the 1850s to now.

The learning flights and walks of bees, wasps and ants are precisely coordinated movements that enable insects to memorise the visual surroundings of their nest or other significant places such as foraging sites. These movements occur on the first few occasions that an insect leaves its nest. They are of special interest because their discovery in the middle of the 19th century provided perhaps the first evidence that insects can learn and are not solely governed by instinct. Here, we recount the history of research on learning flights from their discovery to the present day. The first studies were conducted by skilled naturalists and then, over the following 50 years, by neuroethologists examining the insects' learning behaviour in the context of experiments on insect navigation and its underlying neural mechanisms. The most important property of these movements is that insects repeatedly fixate their nest and look in other favoured directions, either in a preferred compass direction, such as North, or towards preferred objects close to the nest. Nest facing is accomplished through path integration. Memories of views along a favoured direction can later guide an insect's return to its nest. In some ant species, the favoured direction is adjusted to future foraging needs. These memories can then guide both the outward and homeward legs of a foraging trip. Current studies of central areas of the insect brain indicate what regions implement the behavioural manoeuvres underlying learning flights and the resulting visual memories.

5-MeO-DMT modifies innate behaviors and promotes structural neural plasticity in mice.

Serotonergic psychedelics are gaining increasing interest as potential therapeutics for a range of mental illnesses. Compounds with short-lived subjective effects may be clinically useful because dosing time would be reduced, which may improve patient access. One short-acting psychedelic is 5-MeO-DMT, which has been associated with improvement in depression and anxiety symptoms in early phase clinical studies. However, relatively little is known about the behavioral and neural mechanisms of 5-MeO-DMT, particularly the durability of its long-term effects. Here we characterized the effects of 5-MeO-DMT on innate behaviors and dendritic architecture in mice. We showed that 5-MeO-DMT induces a dose-dependent increase in head-twitch response that is shorter in duration than that induced by psilocybin at all doses tested. 5-MeO-DMT also substantially suppresses social ultrasonic vocalizations produced during mating behavior. 5-MeO-DMT produces long-lasting increases in dendritic spine density in the mouse medial frontal cortex that are driven by an elevated rate of spine formation. However, unlike psilocybin, 5-MeO-DMT did not affect the size of dendritic spines. These data provide insights into the behavioral and neural consequences underlying the action of 5-MeO-DMT and highlight similarities and differences with those of psilocybin.

Beyond the Instinct Debate: Daniel Lehrman's Contributions to Animal Behavior Studies.

This paper examines the contributions of Daniel S. Lehrman (1919-1972) to animal behavior studies. Though widely cited as a critic of the early ethological program presented by Konrad Lorenz and Niko Tinbergen, other significant aspects of Lehrman's career and research have not received historical attention. In this paper, I offer a fuller account of Lehrman's work by situating his debate with ethologists within the larger context of Lehrman's early scholarly development under G. K. Noble and T. C. Schneirla, by examining his scientific research on the ring-dove as well as his epistemological views about the best way to understand animal behaviour, and by presenting his leadership in institution and network-building of interdisciplinary approaches to animal behavior. This essay highlights Lehrman's impact on the evolution of ethology, endocrinology, and developmental biology.

Phenotypic plasticity and archetype: a response to common objections to the biological theory of archetype and instinct.

Since Jung's death in 1961, scholars have attempted to integrate growing biological science data into Jungian concepts such as the collective unconscious, instincts and the archetypes. This enterprise has been challenging due to persistent false dichotomies of gene and environment occasionally arising. Recent works by Roesler (2022a, 2022b) for example, have raised objections to the biological theory of archetypes, but the objections are plagued by such dichotomies. The concept of phenotypic plasticity, however, helps to both avoid this problem as well as bridge the gap between competing theories into a more integrated model with solid biological foundations.

Depuis la mort de Jung en 1961, les chercheurs ont tenté d'intégrer les données nouvelles de la biologie avec les concepts Jungiens tels que l'inconscient collectif, les instincts et les archétypes. Cette initiative a rencontré des difficultés car des dichotomies fausses mais tenaces sur le sujet des gènes et de l'environnement se manifestaient. Les travaux récents de Roesler (2022a, 2022b) par exemple ont exprimé des objections à la théorie biologique des archétypes. Cependant ces objections sont biaisées par les dichotomies mentionnées. Le concept de plasticité phénotypique, cependant, aide à la fois à éviter ce problème et à former une passerelle entre des théories rivales et un modèle mieux intégré et doté de solides fondements biologiques.

Desde la muerte de Jung en 1961, académicos han intentado integrar data creciente de las ciencias biológicas a conceptos Junguianos como inconsciente colectivo, instintos y arquetipos. Esta empresa ha sido desafiada debido al surgimiento ocasional de persistentes falsas dicotomías entre genes y medio ambiente. Trabajos recientes de Roesler (2022a, 2022b), por ejemplo, han planteado objeciones a la teoría biológica del arquetipo, pero las objeciones se encuentran afectadas por semejantes dicotomías. El concepto de plasticidad fenotípica, sin embargo, ayuda a evitar este problema, así como a subsanar la brecha entre teorías contrapuestas, hacia un modelo más integrado con fundamentos biógicos sólidos.