scholarly journals Unilateral vocal nerve resection alters neurogenesis in the avian song system in a region-specific manner

PLoS ONE ◽  
2021 ◽  
Vol 16 (8) ◽  
pp. e0256709
Author(s):  
Jake V. Aronowitz ◽  
Alice Perez ◽  
Christopher O’Brien ◽  
Siaresh Aziz ◽  
Erica Rodriguez ◽  
...  
Keyword(s):  
Brain Regions ◽  
Poor Quality ◽  
Adult Brain ◽  
Neuron Survival ◽  
Song System ◽  
Adult Born Neurons ◽  
Caudomedial Nidopallium ◽  
Area X ◽  
Side Dominance ◽  
Avian Song

New neurons born in the adult brain undergo a critical period soon after migration to their site of incorporation. During this time, the behavior of the animal may influence the survival or culling of these cells. In the songbird song system, earlier work suggested that adult-born neurons may be retained in the song motor pathway nucleus HVC with respect to motor progression toward a target song during juvenile song learning, seasonal song restructuring, and experimentally manipulated song variability. However, it is not known whether the quality of song per se, without progressive improvement, may also influence new neuron survival. To test this idea, we experimentally altered song acoustic structure by unilateral denervation of the syrinx, causing a poor quality song. We found no effect of aberrant song on numbers of new neurons in HVC, suggesting that song quality does not influence new neuron culling in this region. However, aberrant song resulted in the loss of left-side dominance in new neurons in the auditory region caudomedial nidopallium (NCM), and a bilateral decrease in new neurons in the basal ganglia nucleus Area X. Thus new neuron culling may be influenced by behavioral feedback in accordance with the function of new neurons within that region. We propose that studying the effects of singing behaviors on new neurons across multiple brain regions that differentially subserve singing may give rise to general rules underlying the regulation of new neuron survival across taxa and brain regions more broadly.

scholarly journals Unilateral vocal nerve resection alters neurogenesis in the avian song system in a region-specific manner

2020 ◽  
Author(s):  
Jake V. Aronowitz ◽  
Alice Perez ◽  
Christopher O’Brien ◽  
Siaresh Aziz ◽  
Erica Rodriguez ◽  
...  
Keyword(s):  
Brain Regions ◽  
Motor Pathway ◽  
Neuron Survival ◽  
Song System ◽  
General Rules ◽  
Caudomedial Nidopallium ◽  
Area X ◽  
Side Dominance ◽  
Avian Song ◽  
Behavioral Feedback

AbstractNew neurons undergo a critical period soon after migration during which the behavior of the animal may result in the survival or culling of these cells. In the songbird song system, new neurons may be maintained in the song motor pathway with respect to motor progression toward a target song--during juvenile song learning, seasonal song restructuring, and experimentally manipulated song variability. However, it is not known whether the quality of song per se, without progressive improvement, may also influence new neuron survival. To test this idea, we experimentally altered song acoustic structure by unilateral denervation of the syrinx. We found no effect of aberrant song on numbers of new neurons in the HVC of the song motor pathway, a loss of left-side dominance in new neurons in the auditory region caudomedial nidopallium (NCM), and a bilateral decrease in new neurons in the basal ganglia nucleus Area X. We propose new neuron survival may be determined in response to behavioral feedback in accordance with the function of new neurons within a given brain region. Studying the effects of singing behaviors on new neurons across multiple brain regions that subserve singing may give rise to general rules underlying the regulation of new neuron survival across taxa and brain regions more broadly.

scholarly journals An architectonic type principle in the development of laminar patterns of cortico-cortical connections

2021 ◽  
Author(s):  
Sarah F. Beul ◽  
Alexandros Goulas ◽  
Claus C. Hilgetag
Keyword(s):  
Structural Connectivity ◽  
Macaque Monkey ◽  
Brain Regions ◽  
Adult Brain ◽  
Mammalian Brain ◽  
Cortical Connections ◽  
Cortical Projections ◽  
Structural Connections ◽  
High Degree ◽  
The Brain

AbstractStructural connections between cortical areas form an intricate network with a high degree of specificity. Many aspects of this complex network organization in the adult mammalian cortex are captured by an architectonic type principle, which relates structural connections to the architectonic differentiation of brain regions. In particular, the laminar patterns of projection origins are a prominent feature of structural connections that varies in a graded manner with the relative architectonic differentiation of connected areas in the adult brain. Here we show that the architectonic type principle is already apparent for the laminar origins of cortico-cortical projections in the immature cortex of the macaque monkey. We find that prenatal and neonatal laminar patterns correlate with cortical architectonic differentiation, and that the relation of laminar patterns to architectonic differences between connected areas is not substantially altered by the complete loss of visual input. Moreover, we find that the degree of change in laminar patterns that projections undergo during development varies in proportion to the relative architectonic differentiation of the connected areas. Hence, it appears that initial biases in laminar projection patterns become progressively strengthened by later developmental processes. These findings suggest that early neurogenetic processes during the formation of the brain are sufficient to establish the characteristic laminar projection patterns. This conclusion is in line with previously suggested mechanistic explanations underlying the emergence of the architectonic type principle and provides further constraints for exploring the fundamental factors that shape structural connectivity in the mammalian brain.

scholarly journals Birdsong Decreases Protein Levels of FoxP2, a Molecule Required for Human Speech

2008 ◽  
Vol 100 (4) ◽  
pp. 2015-2025 ◽  
Author(s):  
Julie E. Miller ◽  
Elizabeth Spiteri ◽  
Michael C. Condro ◽  
Ryan T. Dosumu-Johnson ◽  
Daniel H. Geschwind ◽  
...  
Keyword(s):  
Mrna Expression ◽  
Target Genes ◽  
Expression Patterns ◽  
Vocal Learning ◽  
Brain Regions ◽  
Motor Deficits ◽  
Mrna Levels ◽  
Adult Males ◽  
Protein Levels ◽  
Area X

Cognitive and motor deficits associated with language and speech are seen in humans harboring FOXP2 mutations. The neural bases for FOXP2 mutation-related deficits are thought to reside in structural abnormalities distributed across systems important for language and motor learning including the cerebral cortex, basal ganglia, and cerebellum. In these brain regions, our prior research showed that FoxP2 mRNA expression patterns are strikingly similar between developing humans and songbirds. Within the songbird brain, this pattern persists throughout life and includes the striatal subregion, Area X, that is dedicated to song development and maintenance. The persistent mRNA expression suggests a role for FoxP2 that extends beyond the formation of vocal learning circuits to their ongoing use. Because FoxP2 is a transcription factor, a role in shaping circuits likely depends on FoxP2 protein levels which might not always parallel mRNA levels. Indeed our current study shows that FoxP2 protein, like its mRNA, is acutely downregulated in mature Area X when adult males sing with some differences. Total corticosterone levels associated with the different behavioral contexts did not vary, indicating that differences in FoxP2 levels are not likely attributable to stress. Our data, together with recent reports on FoxP2's target genes, suggest that lowered FoxP2 levels may allow for expression of genes important for circuit modification and thus vocal variability.

scholarly journals Quantitative RT-PCR analyses of five evolutionary conserved genes in Alligator brains during development

2011 ◽  
Vol 2 (4) ◽  
Author(s):  
Sarah Wilson ◽  
Tianli Zhu ◽  
Rajesh Khanna ◽  
Michael Pritz
Keyword(s):  
Gene Expression ◽  
Brain Area ◽  
Brain Regions ◽  
Adult Brain ◽  
Time Interval ◽  
Conserved Genes ◽  
Mrna Gene ◽  
Alligator Mississipiensis ◽  
Mrna Gene Expression ◽  
Present Gene

AbstractGene expression was investigated in the major brain subdivisions (telencephalon, diencephalon, midbrain and hindbrain) in a representative reptile, Alligator mississipiensis, during the later stages of embryonic development. The following genes were examined: voltage-gated sodium channel isoforms: NaV1.1 and NaV1.2; synaptic vesicle 2a (SV2a); synaptophysin; and calbindin 2. With the exception of synaptophysin, which was only expressed in the telencephalon, all genes were expressed in all brain regions sampled at the time periods examined. For NaV1.1, gene expression varied according to brain area sampled. When compared with NaV1.1, the pattern of NaV1.2 gene expression differed appreciably. The gene expression of SV2a was the most robust of any of the genes examined. Of the other genes examined, although differences were noted, no statistically significant changes were found either between brain part or time interval. Although limited, the present analysis is the first quantitative mRNA gene expression study in any reptile during development. Together with future experiments of a similar nature, the present gene expression results should determine which genes are expressed in major brain areas at which times during development in Alligator. When compared with other amniotes, these results will prove useful for determining how gene expression during development influences adult brain structure.

scholarly journals Relationships between dietary macronutrients and adult neurogenesis in the regulation of energy metabolism – CORRIGENDUM

2013 ◽  
Vol 111 (4) ◽  
pp. 755-755
Author(s):  
Marianne A. Yon ◽  
Suzanna L. Mauger ◽  
Lucy C. Pickavance
Keyword(s):  
Body Weight ◽  
Energy Metabolism ◽  
Adult Neurogenesis ◽  
Brain Regions ◽  
The Body ◽  
Adult Brain ◽  
Metabolic Dysfunction ◽  
Neurogenic Niche ◽  
Normal Limits ◽  
Simple Carbohydrates

Of the environmental factors which have an impact on body weight, nutrients are most influential. Within normal limits, hypothalamic and related neuronal populations correct perturbations in energy metabolism, to return the body to its nutritional set-point, either through direct response to nutrients or indirectly via peripheral appetite signals. Excessive intake of certain macronutrients, such as simple carbohydrates and SFA, can lead to obesity and attendant metabolic dysfunction, also reflected in alterations in structural plasticity, and, intriguingly, neurogenesis, in some of these brain regions. Neurogenesis, previously thought to occur only in the embryo, is now known to take place in the adult brain, dependent on numerous stimulating and inhibiting factors, including dietary components. Because of classic associations between neurogenesis and the hippocampus, in learning and cognition, this brain region has also been the focus of attention in the study of links between diet and neurogenesis. Recently, however, a more complete picture of this relationship has been building: not only has the hypothalamus been shown to satisfy the criteria for a neurogenic niche, but appetite-related mediators, including circulating hormones, such as leptin and ghrelin, pro-inflammatory cytokines and the endocannabinoid intracellular messengers, are also being examined for their potential role in mediating neurogenic responses to macronutrients. The present review draws together these observations and investigates whether n-3 PUFA may exert their attenuating effects on body weight through the stimulation of adult neurogenesis. Exploration of the effects of nutraceuticals on neurogenic brain regions may encourage the development of new rational therapies in the fight against obesity.

scholarly journals Species variation in the degree of sex differences in brain and behaviour related to birdsong: adaptations and constraints

2016 ◽  
Vol 371 (1688) ◽  
pp. 20150117 ◽  
Author(s):  
Gregory F. Ball
Keyword(s):  
Sex Differences ◽  
Neural Circuit ◽  
Species Variation ◽  
Song System ◽  
System A ◽  
Song Control System ◽  
Males And Females ◽  
Song Control ◽  
Area X ◽  
The Brain

The song-control system, a neural circuit that controls the learning and production of birdsong, provided the first example in vertebrates of prominent macro-morphological sex differences in the brain. Forebrain nuclei HVC, robust nucleus of the arcopallium (RA) and area X all exhibit prominent male-biased sex differences in volume in zebra finches and canaries. Subsequent studies compared species that exhibited different degrees of a sex difference in song behaviour and revealed an overall positive correlation between male biases in song behaviour and male biases in the volume of the song nuclei. However, several exceptions have been described in which male biases in HVC and RA are observed even though song behaviour is equal or even female-biased. Other phenotypic measures exhibit lability in both sexes. In the duetting plain-tailed wren ( Pheugopedius euophrys ), males and females have auditory cells in the song system that are tuned to the joint song the two sexes produce rather than just male or female components. These findings suggest that there may be constraints on the adaptive response of the song system to ecological conditions as assessed by nucleus volume but that other critical variables regulating song can respond so that each sex can modify its song behaviour as needed.

scholarly journals The Antennal Pathway of Dragonfly Nymphs, from Sensilla to the Brain

Insects ◽  
2020 ◽  
Vol 11 (12) ◽  
pp. 886
Author(s):  
Silvana Piersanti ◽  
Manuela Rebora ◽  
Gianandrea Salerno ◽  
Sylvia Anton
Keyword(s):  
Brain Structure ◽  
Antennal Lobe ◽  
Sensory Information ◽  
Brain Structures ◽  
Brain Regions ◽  
Adult Brain ◽  
Published Data ◽  
Antennal Sensilla ◽  
Aquatic Life ◽  
The Brain

Dragonflies are hemimetabolous insects, switching from an aquatic life style as nymphs to aerial life as adults, confronted to different environmental cues. How sensory structures on the antennae and the brain regions processing the incoming information are adapted to the reception of fundamentally different sensory cues has not been investigated in hemimetabolous insects. Here we describe the antennal sensilla, the general brain structure, and the antennal sensory pathways in the last six nymphal instars of Libellula depressa, in comparison with earlier published data from adults, using scanning electron microscopy, and antennal receptor neuron and antennal lobe output neuron mass-tracing with tetramethylrhodamin. Brain structure was visualized with an anti-synapsin antibody. Differently from adults, the nymphal antennal flagellum harbors many mechanoreceptive sensilla, one olfactory, and two thermo-hygroreceptive sensilla at all investigated instars. The nymphal brain is very similar to the adult brain throughout development, despite the considerable differences in antennal sensilla and habitat. Like in adults, nymphal brains contain mushroom bodies lacking calyces and small aglomerular antennal lobes. Antennal fibers innervate the antennal lobe similar to adult brains and the gnathal ganglion more prominently than in adults. Similar brain structures are thus used in L. depressa nymphs and adults to process diverging sensory information.

scholarly journals Use of PG-21 immunocytochemistry to detect androgen receptors in the songbird brain.

1996 ◽  
Vol 44 (9) ◽  
pp. 1075-1080 ◽  
Author(s):  
G T Smith ◽  
E A Brenowitz ◽  
G S Prins
Keyword(s):  
Androgen Receptor ◽  
Neural Plasticity ◽  
Behavioral Plasticity ◽  
Androgen Receptors ◽  
Brain Regions ◽  
Cell Nuclei ◽  
Low Concentrations ◽  
Song Control System ◽  
Song Control ◽  
Avian Song

The avian song control system is an excellent model in which to study the effects of gonadal steroid hormones on neural and behavioral plasticity. Several of the brain regions that control song behavior concentrate androgens and/or estrogens. Investigations of the distribution and regulation of androgen receptors have been limited by the lack of a reliable immunocytochemical method to detect androgen receptors in the songbird brain. We describe a protocol by which the PG-21 polygonal antibody to the rat androgen receptor can be used to label androgen receptor-containing cells in the songbird brain. By treating songbirds of several species with testosterone 90 min before sacrifice and by using relatively low concentrations (0.5 0.75 microg/ml) of PG-21 antibody to reduce nonspecific background staining, we were able to obtain strong specific labeling of cell nuclei in androgen-sensitive brain regions. This technique will facilitate the study of the role of androgens in mediating neural plasticity in the avian brain. Testosterone pretreatment may also facilitate the use of this antibody to label androgen receptors in tissues from a wide array of nonmammalian species.

Phasic basal ganglia activity associated with high-gamma oscillation during sleep in a songbird

2012 ◽  
Vol 107 (1) ◽  
pp. 424-432 ◽  
Author(s):  
Shin Yanagihara ◽  
Neal A. Hessler
Keyword(s):  
Basal Ganglia ◽  
Phase Locking ◽  
Critical Role ◽  
Field Potential ◽  
Vocal Plasticity ◽  
Song System ◽  
Gamma Frequency ◽  
High Gamma ◽  
Area X

The basal ganglia is thought to be critical for motor control and learning in mammals. In specific basal ganglia regions, gamma frequency oscillations occur during various behavioral states, including sleeping periods. Given the critical role of sleep in regulating vocal plasticity of songbirds, we examined the presence of such oscillations in the basal ganglia. In the song system nucleus Area X, epochs of high-gamma frequency (80–160 Hz) oscillation of local field potential during sleep were associated with phasic increases of neural activity. While birds were awake, activity of the same neurons increased specifically when birds were singing. Furthermore, during sleep there was a clear tendency for phase locking of spikes to these oscillations. Such patterned activity in the sleeping songbird basal ganglia could play a role in off-line processing of song system motor networks.

Sign in / Sign up

Export Citation Format

Share Document