Chihiro Mori's research while affiliated with Teikyo University and other places

... BF is a domesticated strain of the wild ancestor WRM, and a growing body of research suggests that in the course of the domestication process, BFs have acquired behavioral, anatomical, and neuroendocrine changes, including reduced sensitivity to environmental stresses (Suzuki et al., 2014;Tobari et al., 2022). In particular, BFs exhibit reduced levels of fearfulness related to coping with predation (Suzuki et al., 2013) and lower fecal CORT levels than WRM (Suzuki et al., 2012). ...

... Another possible explanation for these results could be a sex difference in vocal plasticity. A recent study in canaries found that motor driven ZENK expression in the RA of male canaries was signi cantly decreased in the spring when song was crystalized compared to their more plastic fall singing (Hayase et al. 2021). Therefore, it is possible that female RCCBs have more plastic song than their male counterparts, which could lead to the sex differences we found in the degree of motor-driven ZENK expression in RA. ...

... Curiosity, for instance, is a form of intrinsic motivation, which is well-exhibited by infants and children [108]. Another example is the completely intrinsic desire of a songbird to sing in isolation, despite it not necessarily being beneficial to the bird [143]. On the other hand, external motivation can be presented in the form of goals or rewards in the environment, either in concrete form, such as food, or abstract, such as appreciation. ...

... These mixed asocial/socially learned communication systems are not limited to humans. Bird song across 15 species show an organizational pattern (Menzerath's law) that is also found in human speech, music, and other animal communication (James et al., 2021). While this structure was hypothesized to be socially learned, this recent study suggested that it is due to performance, or even physiological constraints. ...

... To mark potential HVC postsynaptic targets, we sparsely labelled HVC-RA projection neurons with tdTomato. To accomplish this, we first electrophysiologically identified RA with a tungsten electrode (0.5 MΩ, MicroProbes) and injected 50 nl of a retrograde Cre-encoding virus diluted in physiological saline solution into its centre (1:20 dilution; scAAV-DJ9-hCMV-CRE) 50 . Then, 200 nl of Credependent tdTomato virus (AAV9-FLEX-tdTomato; Addgene, 28306-AAV9) was injected into HVC. ...

... Although both SNc and SNr have been shown to participate in sleep-wake control and motor behavior regulation, SNc and SNr are different histologically. SNc is involved in the modulation of sleep-wake through dopaminergic neurons (Yanagihara et al., 2020), while SNr is integrated with GABAergic neurons (Liu et al., 2020). More studies are needed to decipher the mechanisms underlying the selective distribution of orexin fibers. ...

... In addition, juvenile songbirds are endowed with neural processes that bias them to learn species-typical sounds and sequences (e.g., Fehér et al., 2009;Gardner et al., 2005;James & Sakata, 2017;Marler & Peters, 1977;Plamondon et al., 2008; ter Haar et al., 2014;Whaling et al., 1997;reviewed in Sakata & Woolley, 2020). For example, when juvenile zebra finches are tutored with randomized and unbiased sequences of species-typical acoustic elements, they converge on acoustic patterns that are commonly observed in wild and laboratory populations of zebra finches (James & Sakata, 2017;James et al., 2020). Songbirds like the zebra finch are also excellent to understand the temporal organization of vocalizations because activity in discrete areas of their brains regulates song tempo (Ali et al., 2013;Long & Fee, 2008;Scharff & Nottebohm, 1991;Zhang et al., 2017) and because sensory responses of auditory neurons are sensitive to song tempo, including the durations of silent gaps between song elements (Araki et al., 2016;Bee & Klump, 2005;Bouchard & Brainard, 2016;Lampen et al., 2014;Lim et al., 2016). ...

... Neither receptor is evident in the primary auditory pallium Field L (Kubikova et al., 2010). Neurons in the ventral tegmental area have been reported to project to the NCM and could provide a learning-contingent source of dopamine to this region (Yanagihara et al., 2019). Indeed, hearing song increases rapid turnover of dopamine in songbird auditory regions, especially in the NCM (Matragrano et al., 2012). ...

... mean±sem, two-sided Wilcoxon rank-sum test p = 5e-4). Singing influences gene expression in the song system (Feenders et al., 2008;Horita et al., 2012;Jarvis et al., 1998;Sasaki et al., 2006;Wada et al., 2006;Warren et al., 2010;Whitney et al., 2014;Whitney and Johnson, 2005), and previous work has indicated that recent singing influences song plasticity and variability (Chen et al., 2013;Hayase et al., 2018;Hilliard et al., 2012;Miller et al., 2010;Ohgushi et al., 2015). Therefore, we also included terms for the number of songs sung on the day of euthanasia and the average number of songs sung per day in the pre-procedure period to control for constitutive differences in singing propensity. ...

... In the green module, genes encoded receptors related to dopamine, serotonin and acetylcholine signalling. These systems are broadly involved in modulation of locomotion, reward, reinforcement, memory and learning (Wise, 2004), including learning and production of bird song (Asogwa et al., 2018;Heimovics & Riters, 2008;Kubikova & Košťál, 2010;Yip et al., 2020). Our results extend previous connections between heat and dopamine, serotonin and acetylcholine signalling (e.g., Kim et al., 2013;Ray et al., 2011;Shibasaki et al., 2002), by relating the degree of behavioural thermoregulation to variation in heat-induced gene regulation in the brain. ...