Abstract:The song system of songbirds (oscines) is one of the best studied neuroethological model systems. So far, it has been treated as a relatively constrained sensorimotor system. Songbirds such as crows, however, are also known for their capability to cognitively control their audio‐vocal system. Yet, the neuroanatomy of the corvid song system has never been explored systematically. We aim to close this scientific gap by presenting a stereotactic investigation of the extended song system of the carrion crow (Corvu… Show more
“…Four staining protocols were applied to alternating sections (Kersten et al., 2021). For the first series of every brain, a Nissl stain (0.1% cresyl violet) was applied; the second series was stained for myelin (using 0.2% gold chloride solution; Schmued, 1990), while the third series was stained for both Nissl and myelin by combining the staining protocols.…”
Section: Methodsmentioning
confidence: 99%
“…A volume increase in associative pallial structures and particularly high associative neuron numbers seem to accompany enhanced cognitive skills in corvids (Burish et al., 2004; Iwaniuk & Hurd, 2005; Mehlhorn et al., 2010; Rehkämper et al., 1991; Ströckens et al., 2022). However, with the exception of a few specialized neuroanatomical studies (Izawa & Wiatanabe, 2007; Kersten et al., 2021; Sen et al., 2019; von Eugen et al., 2020), a detailed brain atlas of the corvid brain is lacking.…”
Corvidae, passerine songbirds such as jays, crows, and ravens known as corvids, have become model systems for the study of avian cognition. The superior cognitive capabilities of corvids mainly emerge from a disproportionally large telencephalon found in these species. However, a systematic mapping of the neuroanatomy of the corvid brain, and the telencephalon in particular, is lacking so far. Here, we present a brain atlas of the carrion crow, Corvus corone, with special emphasis on the telencephalic pallium. We applied four staining techniques to brain slices (Nissl, myelin, combination of Nissl and myelin, and tyrosine hydroxylase targeting catecholaminergic neurons). This allowed us to identify brain nuclei throughout the brain and delineate the known pallial subdivisions termed hyperpallium, entopallium, mesopallium, nidopallium, arcopallium, and hippocampal complex. The extent of these subdivisions and brain nuclei are described according to stereotaxic coordinates. In addition, 3D depictions of pallial regions were reconstructed from these slices. While the overall organization of the carrion crow's brain matches other songbird brains, the relative proportions and expansions of associative pallial areas differ considerably in agreement with enhanced cognitive skills found in corvids. The presented global organization of the crow brain in stereotaxic coordinates will help to guide future neurobiological studies in corvids.
“…Four staining protocols were applied to alternating sections (Kersten et al., 2021). For the first series of every brain, a Nissl stain (0.1% cresyl violet) was applied; the second series was stained for myelin (using 0.2% gold chloride solution; Schmued, 1990), while the third series was stained for both Nissl and myelin by combining the staining protocols.…”
Section: Methodsmentioning
confidence: 99%
“…A volume increase in associative pallial structures and particularly high associative neuron numbers seem to accompany enhanced cognitive skills in corvids (Burish et al., 2004; Iwaniuk & Hurd, 2005; Mehlhorn et al., 2010; Rehkämper et al., 1991; Ströckens et al., 2022). However, with the exception of a few specialized neuroanatomical studies (Izawa & Wiatanabe, 2007; Kersten et al., 2021; Sen et al., 2019; von Eugen et al., 2020), a detailed brain atlas of the corvid brain is lacking.…”
Corvidae, passerine songbirds such as jays, crows, and ravens known as corvids, have become model systems for the study of avian cognition. The superior cognitive capabilities of corvids mainly emerge from a disproportionally large telencephalon found in these species. However, a systematic mapping of the neuroanatomy of the corvid brain, and the telencephalon in particular, is lacking so far. Here, we present a brain atlas of the carrion crow, Corvus corone, with special emphasis on the telencephalic pallium. We applied four staining techniques to brain slices (Nissl, myelin, combination of Nissl and myelin, and tyrosine hydroxylase targeting catecholaminergic neurons). This allowed us to identify brain nuclei throughout the brain and delineate the known pallial subdivisions termed hyperpallium, entopallium, mesopallium, nidopallium, arcopallium, and hippocampal complex. The extent of these subdivisions and brain nuclei are described according to stereotaxic coordinates. In addition, 3D depictions of pallial regions were reconstructed from these slices. While the overall organization of the carrion crow's brain matches other songbird brains, the relative proportions and expansions of associative pallial areas differ considerably in agreement with enhanced cognitive skills found in corvids. The presented global organization of the crow brain in stereotaxic coordinates will help to guide future neurobiological studies in corvids.
“…Glass-coated tungsten microelectrodes with 2 MΩ impedance (Alpha Omega) were used. The electrodes targeted the corvid NCL, which is characterized by dopaminergic cells 63 – 65 . Each recording session started with adjusting the electrodes, until a proper neuronal signal (of at least 3:1 signal to noise) was detected on at least one channel (see also Fig.…”
Section: Methodsmentioning
confidence: 99%
“…We verified the NCL and the location of the electrodes in NCL (according to the implantation coordinates provided above). We immunohistochemically stained for tyrosine hydroxylase to identify dopaminergic cells, which characterize the NCL 65 (see Fig. 3 in Veit and Nieder 63 ).…”
The nidopallium caudolaterale (NCL), an integration centre in the telencephalon of birds, plays a crucial role in representing and maintaining abstract categories and concepts. However, the computational principles allowing pallial microcircuits consisting of excitatory and inhibitory neurons to shape the tuning to abstract categories remain elusive. Here we identified the major pallial cell types, putative excitatory projection cells and inhibitory interneurons, by characterizing the waveforms of action potentials recorded in crows performing a cognitively demanding numerical categorization task. Both cell types showed clear differences in their capacity to encode categorical information. Nearby and functionally coupled putative projection neurons generally exhibited similar tuning, whereas putative interneurons showed mainly opposite tuning. The results favour feedforward mechanisms for the shaping of categorical tuning in microcircuits of the NCL. Our findings help to decipher the workings of pallial microcircuits in birds during complex cognition and to compare them vis-a-vis neocortical processes in mammals.
“…Such coordinated actions require acute senses (Iwaniuk and Wylie, 2020), but most of all delicate motor planning and motor execution capabilities (Davies and Green, 1994;Brecht et al, 2019). With the exception of birdsong research, a research area that resulted in detailed knowledge on the neuroanatomy and neurophysiology of song production (Elemans, 2014;Schmidt and Wild, 2014;Murphy et al, 2017;Kersten et al, 2021), and despite the solid understanding of the neuroanatomy of the avian motor system (Dubbeldam, 2000), the neurophysiological mechanisms of motor plans and actions are rarely explored in birds. This is particularly true for cognitively-controlled and intentional motor plans that in corvid songbirds are comparable to those found in primates (Kabadayi et al, 2016;Miller et al, 2019).…”
The planning and execution of head-beak movements are vital components of bird behavior. They require integration of sensory input and internal processes with goal-directed motor output. Despite its relevance, the neurophysiological mechanisms underlying action planning and execution outside of the song system are largely unknown. We recorded single-neuron activity from the associative endbrain area nidopallium caudolaterale (NCL) of two male carrion crows (Corvus corone) trained to plan and execute head-beak movements in a spatial delayed response task. The crows were instructed to plan an impending movement toward one of eight possible targets on the left or right side of a touchscreen. In a fraction of trials, the crows were prompted to plan a movement toward a self-chosen target. NCL neurons signaled the impending motion direction in instructed trials. Tuned neuronal activity during motor planning categorically represented the target side, but also specific target locations. As a marker of intentional movement preparation, neuronal activity reliably predicted both target side and specific target location when the crows were free to select a target. In addition, NCL neurons were tuned to specific target locations during movement execution. A subset of neurons was tuned during both planning and execution period; these neurons experienced a sharpening of spatial tuning with the transition from planning to execution. These results show that the avian NCL not only represents high-level sensory and cognitive task components, but also transforms behaviorally-relevant information into dynamic action plans and motor execution during the volitional perception-action cycle of birds.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.