scholarly journals Drosophila acquires seconds-scale rhythmic behavior

2021 ◽  
pp. jeb.242443
Author(s):  
Masayoshi Ikarashi ◽  
Hiromu Tanimoto
Keyword(s):  
Temporal Structure ◽  
Interval Timing ◽  
Fruit Fly ◽  
Conditioning Paradigm ◽  
Time Frequency ◽  
Behavioral Rhythms ◽  
Behavioral Adaptations ◽  
Electric Shocks ◽  
Rhythmic Behavior ◽  
Temporal Conditioning

Detection of the temporal structure of stimuli is crucial for prediction. While perception of interval timing is relevant for immediate behavioral adaptations, it has been scarcely investigated, especially in invertebrates. Here we examined if the fruit fly, Drosophila melanogaster, can acquire rhythmic behavior in the range of seconds. To this end, we developed a novel temporal conditioning paradigm utilizing repeated electric shocks. Combined automatic behavioral annotation and time-frequency analysis revealed that behavioral rhythms continued after cessation of the shocks. Furthermore, we found that aging impaired interval timing. This study thus not only demonstrated the ability of insects to acquire behavioral rhythms of a few seconds, but highlighted a life-course decline of temporal coordination, that is common also in mammals.

scholarly journals EEG-Based 3D Visual Fatigue Evaluation Using CNN

Electronics ◽  
2019 ◽  
Vol 8 (11) ◽  
pp. 1208 ◽  
Author(s):  
Kang Yue ◽  
Danli Wang
Keyword(s):  
Feature Extraction ◽  
Temporal Structure ◽  
Visual Fatigue ◽  
Eeg Signals ◽  
Visual Evaluation ◽  
Time Frequency ◽  
Multi Scale ◽  
Temporal Features ◽  
Depth Analysis ◽  
Fatigue Evaluation

Visual fatigue evaluation plays an important role in applications such as virtual reality since the visual fatigue symptoms always affect the user experience seriously. Existing visual evaluation methods require hand-crafted features for classification, and conduct feature extraction and classification in a separated manner. In this paper, we conduct a designed experiment to collect electroencephalogram (EEG) signals of various visual fatigue levels, and present a multi-scale convolutional neural network (CNN) architecture named MorletInceptionNet to detect visual fatigue using EEG as input, which exploits the spatial-temporal structure of multichannel EEG signals. Our MorletInceptionNet adopts a joint space-time-frequency features extraction scheme in which Morlet wavelet-like kernels are used for time-frequency raw feature extraction and inception architecture are further used to extract multi-scale temporal features. Then, the multi-scale temporal features are concatenated and fed to the fully connected layer for visual fatigue evaluation using classification. In experiment evaluation, we compare our method with five state-of-the-art methods, and the results demonstrate that our model achieve overally the best performance better performance for two widely used evaluation metrics, i.e., classification accuracy and kappa value. Furthermore, we use input-perturbation network-prediction correlation maps to conduct in-depth analysis into the reason why the proposed method outperforms other methods. The results suggest that our model is sensitive to the perturbation of β (14–30 Hz) and γ (30–40 Hz) bands. Furthermore, their spatial patterns are of high correlation with that of the corresponding power spectral densities which are used as evaluation features traditionally. This finding provides evidence of the hypothesis that the proposed model can learn the joint time-frequency-space features to distinguish fatigue levels automatically.

Random Mating amongAnastrepha ludens(Diptera: Tephritidae) Adults of Geographically Distant and Ecologically Distinct Populations in Mexico

2008 ◽  
Vol 99 (2) ◽  
pp. 207-214 ◽  
Author(s):  
M. Aluja ◽  
J. Rull ◽  
D. Pérez-Staples ◽  
F. Díaz-Fleischer ◽  
J. Sivinski
Keyword(s):  
Environmental Conditions ◽  
Large Scale ◽  
Random Mating ◽  
Fruit Fly ◽  
Anastrepha Ludens ◽  
South American ◽  
Field Cage ◽  
Local Conditions ◽  
Behavioral Adaptations ◽  
Males And Females

AbstractThe Mexican fruit flyAnastrepha ludens(Loew) (Diptera: Tephritidae) is a polyphagous pestiferous insect with a geographical range encompassing highly variable environmental conditions. Considering that cryptic species have been recently found among South American representatives of the same taxonomic group asA. ludens, we tested whether or not some populations ofA. ludenshave evolved assortative mating as an isolating mechanism that maintains intrapopulation genetic differences and behavioral adaptations to local conditions. Males and females stemming from widely separated locations with similar environmental conditions and males and females stemming from populations within individual-flight range, but collected in different hosts (a native and an exotic one), mated randomly amongst themselves when placed in a field cage. Despite the fact that sibling males and females from two distinct populations also mated randomly amongst themselves, siblings engaged in significantly longer copulations than non-siblings, indicating that perhaps adults discriminated mates with similar genetic compositions. Our results have important practical implications asA. ludensis the most devastating pest of citrus in Mexico and Central America, and large-scale releases of sterile flies are used to control it.

scholarly journals Dosage compensation of the period gene in Drosophila melanogaster.

Genetics ◽  
1994 ◽  
Vol 138 (3) ◽  
pp. 721-732
Author(s):  
M K Cooper ◽  
M J Hamblen-Coyle ◽  
X Liu ◽  
J E Rutila ◽  
J C Hall
Keyword(s):  
Drosophila Melanogaster ◽  
Dosage Compensation ◽  
Gene Dosage ◽  
Genetic Locus ◽  
Fruit Fly ◽  
Regulatory Control ◽  
Biological Clocks ◽  
Period Gene ◽  
Behavioral Rhythms ◽  
The One

Abstract The period (per) gene is located on the X chromosome of Drosophila melanogaster. Its expression influences biological clocks in this fruit fly, including the one that subserves circadian rhythms of locomotor activity. Like most X-linked genes in Drosophila, per is under the regulatory control of gene dosage compensation. In this study, we assessed the activity of altered or augmented per+ DNA fragments in transformants. Relative expression levels in male and female adults were inferred from periodicities associated with locomotor behavioral rhythms, and by histochemically assessing beta-galactosidase levels in transgenics carrying different kinds of per-lacZ fusion genes. The results suggest that per contains multipartite regulatory information for dosage compensation within the large first intron and also within the 3' half of this genetic locus.

scholarly journals A temperature-dependent molecular switch to adjust behavior to changing environmental conditions

2020 ◽  
Author(s):  
Chenghao Chen ◽  
Min Xu ◽  
Paola Correa ◽  
Ralf Stanewsky
Keyword(s):  
Molecular Clock ◽  
Clock Genes ◽  
Clock Synchronization ◽  
Feedback Regulation ◽  
Fruit Fly ◽  
Constant Light ◽  
Negative Feedback Regulation ◽  
Temperature Cycles ◽  
Behavioral Rhythms ◽  
Northern Latitudes

SummaryCircadian clocks increase fitness of organisms by adapting physiological and behavioral rhythms to the daily changes of light and temperature, caused by the Earth’ 24-hr rotation around its own axis. They consist of self-sustained molecular oscillators, maintained by negative feedback regulation of several clock genes, including period (per) and timeless (tim) in the fruit fly Drosophila melanogaster. This molecular clock is synchronized by light:dark and temperature cycles (Zeitgeber), and in turn drives rhythmic biological outputs, like the daily locomotor activity rhythms. While light generally is considered to be the more dominant, daily temperature cycles are sufficient for stable circadian clock synchronization. In Drosophila constant light leads to break down of the molecular clock and arrhythmic behavior, but clock function can be restored by simultaneously exposing the flies to temperature cycles, indicating their particular importance in regions experiencing long photoperiods or constant light. Here, we reveal that during temperature cycles, the deleterious effects of constant light on the clock are avoided by repressing the activity of the photoreceptor CRYPTOCHROME (CRY), which normally leads to light-dependent degradation of TIM. We show that CRY levels are repressed by Gq-PLC-ß signaling, operating within central clock neurons, thereby stabilizing TIM and promoting clock function during constant light and temperature cycles. Consistent with these findings, we reveal that a recently evolved and less light sensitive form of TIM, does not require Gq-PLC-ß signaling for maintaining clock function during constant light and temperature cycles. In summary, our results supply the molecular explanation for temperature synchronization in constant light, and how fruit flies can maintain clock function and rhythmic behavior in northern latitudes.

Visualization of EEG Using Time-Frequency Distributions

1997 ◽  
Vol 36 (04/05) ◽  
pp. 298-301 ◽  
Author(s):  
B. Stiber ◽  
S. Sato
Keyword(s):  
Brain Activity ◽  
Temporal Structure ◽  
Frequency Resolution ◽  
Signal Frequency ◽  
Time Varying ◽  
Eeg Analysis ◽  
Frequency Distributions ◽  
Time Frequency ◽  
Temporal Features ◽  
Time Varying Frequency

Abstract:The EEG is a time-varying or nonstationary signal. Frequency and amplitude are two of its significant characteristics, and are valuable clues to different states of brain activity. Detection of these temporal features is important in understanding EEGs. Commonly, spectrograms and AR models are used for EEG analysis. However, their accuracy is limited by their inherent assumption of stationarity and their trade-off between time and frequency resolution. We investigate EEG signal processing using existing compound kernel time-frequency distributions (TFDs). By providing a joint distribution of signal intensity at any frequency along time, TFDs preserve details of the temporal structure of the EEG waveform, and can extract its time-varying frequency and amplitude features. We expect that this will have significant implications for EEG analysis and medical diagnosis.

scholarly journals Extinction-resistant attention to long-term conditioned threat is indexed by selective visuocortical alpha suppression in humans

2019 ◽  
Author(s):  
Christian Panitz ◽  
Andreas Keil ◽  
Erik M. Mueller
Keyword(s):  
Visual Attention ◽  
Crucial Role ◽  
Recall Test ◽  
Alpha Power ◽  
Conditioning Paradigm ◽  
Time Frequency ◽  
Long Term Stability ◽  
First Time

AbstractWhile ERP studies have shown heightened early visual attention to conditioned threat, it is unknown whether this attentional prioritization is sustained throughout later processing stages and whether it is robust to extinction. To investigate sustained visual attention, we assessed visuocortical alpha suppression in response to conditioned and extinguished threat. N = 87 participants underwent a two-day threat conditioning paradigm with acquisition and extinction on one day and a critical recall test one day later. EEG time-frequency analyses revealed that, on Day 2, threat-conditioned vs. safety cues evoked stronger occipital alpha power suppression from 600 to 1200 ms. Notably, this suppression was resistant to extinction. The present study showed for the first time that threat conditioning enhances sustained modulation of visuocortical attention to threat in the long term. The long-term stability and extinction resistance of alpha suppression suggests a crucial role of visuocortical attention mechanisms in the maintenance of learned fears.

scholarly journals Zebrafish forebrain and temporal conditioning

2014 ◽  
Vol 369 (1637) ◽  
pp. 20120462 ◽  
Author(s):  
Ruey-Kuang Cheng ◽  
Suresh J. Jesuthasan ◽  
Trevor B. Penney
Keyword(s):  
Single Cell ◽  
Single Cells ◽  
Model Organism ◽  
Interval Timing ◽  
Whole Brain ◽  
Larval Zebrafish ◽  
Vertebrate Brain ◽  
Neuroscience Research ◽  
Temporal Conditioning ◽  
Precise Time

The rise of zebrafish as a neuroscience research model organism, in conjunction with recent progress in single-cell resolution whole-brain imaging of larval zebrafish, opens a new window of opportunity for research on interval timing. In this article, we review zebrafish neuroanatomy and neuromodulatory systems, with particular focus on identifying homologies between the zebrafish forebrain and the mammalian forebrain. The neuroanatomical and neurochemical basis of interval timing is summarized with emphasis on the potential of using zebrafish to reveal the neural circuits for interval timing. The behavioural repertoire of larval zebrafish is reviewed and we demonstrate that larval zebrafish are capable of expecting a stimulus at a precise time point with minimal training. In conclusion, we propose that interval timing research using zebrafish and whole-brain calcium imaging at single-cell resolution will contribute to our understanding of how timing and time perception originate in the vertebrate brain from the level of single cells to circuits.

Closely Related Fruit Fly Species Living at Different Latitudes Diverge in Their Circadian Clock Anatomy and Rhythmic Behavior

2018 ◽  
Vol 33 (6) ◽  
pp. 602-613 ◽  
Author(s):  
Marta Beauchamp ◽  
Enrico Bertolini ◽  
Peter Deppisch ◽  
Jonathan Steubing ◽  
Pamela Menegazzi ◽  
...  
Keyword(s):  
Circadian Clock ◽  
High Latitude ◽  
Expression Patterns ◽  
Fruit Fly ◽  
Adaptive Significance ◽  
High Latitudes ◽  
Pigment Dispersing Factor ◽  
Clock Network ◽  
Rhythmic Behavior ◽  
And Behavior

Recently, we reported differences in the expression pattern of the blue light-sensitive flavoprotein cryptochrome (CRY) and the neuropeptide pigment-dispersing factor (PDF) in the neuronal clock network of high-latitude Drosophila species, belonging to the Drosophila subgenus ( virilis-repleta radiation), compared with cosmopolitan D. melanogaster flies, belonging to the Sophophora subgenus. Alterations in rhythmic patterns of activity due to these differences might have adaptive significance for colonizing high-latitude habitats and, hence, adjusting to long photoperiods. Here, we show that these differing CRY/PDF expression patterns are only present in those species of the virilis-repleta radiation that colonized high latitudes. The cosmopolitan species D. mercatorum and D. hydei have a D. melanogaster-like clock network and behavior despite belonging to the virilis-repleta radiation. Similarly, 2 species of the holotropical Zaprionus genus, more closely related to the Drosophila subgenus than to the Sophophora subgenus, retain a D. melanogaster-like clock network and rhythmic behavior. We therefore suggest that the D. melanogaster-like clock network is the “ancestral fly clock phenotype” and that alterations in the CRY/PDF clock neurochemistry have allowed some species of the virilis-repleta radiation to colonize high-latitude environments.

Sign in / Sign up

Export Citation Format

Share Document