Two Alternating Motor Programs Drive Navigation in Drosophila Larva

The control of movements is a fundamental feature shared by all animals. At the most basic level, simple movements are generated by coordinated neural activity and muscle contraction patterns that are controlled by the central nervous system. How behavioral responses to various sensory inputs are processed and integrated by the downstream neural network to produce flexible and adaptive behaviors remains an intense area of investigation in many laboratories. Due to recent advances in experimental techniques, many fundamental neural pathways underlying animal movements have now been elucidated. For example, while the role of motor neurons in locomotion has been studied in great detail, the roles of interneurons in animal movements in both basic and noxious environments have only recently been realized. However, the genetic and transmitter identities of many of these interneurons remains unclear. In this review, we provide an overview of the underlying circuitry and neural pathways required by Drosophila larvae to produce successful movements. By improving our understanding of locomotor circuitry in model systems such as Drosophila, we will have a better understanding of how neural circuits in organisms with different bodies and brains lead to distinct locomotion types at the organism level. The understanding of genetic and physiological components of these movements types also provides directions to understand movements in higher organisms.

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Handwriting in Alzheimer’s Disease

Journal of Alzheimer s Disease ◽

10.3233/jad-210279 ◽

2021 ◽

pp. 1-9

Author(s):

Margarete Delazer ◽

Laura Zamarian ◽

Atbin Djamshidian

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Clinical Course ◽

Typical Feature ◽

Healthy Controls ◽

Spearman Correlation ◽

Writing Difficulties ◽

Motor Programs ◽

Processing Level ◽

Diagnostic Values

Background: Agraphia is a typical feature in the clinical course of Alzheimer’s disease (AD). Objective: Assess the differences between AD and normal aging as regards kinematographic features of handwriting and elucidate writing deficits in AD. Methods: The study included 23 patients with AD (78.09 years/SD = 7.12; MMSE 21.39/SD = 3.61) and 34 healthy controls (75.56 years/SD = 5.85; MMSE 29.06/SD = 0.78). Both groups performed alphabetical and non-alphabetical writing tasks. The kinematographic assessment included the average number of inversions per stroke (NIV; number of peaks in the velocity profile in a single up or down stroke), percentage of automated segments, frequency (average number of strokes per second), writing pressure, and writing velocity on paper. Results: A total of 14 patients showed overt writing difficulties reflected by omissions or substitutions of letters. AD patients showed less automated movements (as measured by NIV), lower writing velocity, and lower frequency of up-and-down strokes in non-alphabetical as well as in alphabetical writing. In the patient group, Spearman correlation analysis between overt writing performance and NIV was significant. That means patients who had less errors in writing a sentence showed a higher automaticity in handwriting. The correctness of alphabetical writing and some kinematographic measures in writing non-alphabetical material reached excellent diagnostic values in ROC analyses. There was no difference in the application of pressure on the pen between patients and controls. Conclusion: Writing disorders are multi-componential in AD and not strictly limited to one processing level. The slow and poorly automated execution of motor programs is not bound to alphabetical material.

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Modulatory effects on Drosophila larva hearts: room temperature, acute and chronic cold stress

Journal of Comparative Physiology B ◽

10.1007/s00360-016-0997-x ◽

2016 ◽

Vol 186 (7) ◽

pp. 829-841 ◽

Cited By ~ 15

Author(s):

Yue Chen Zhu ◽

Emily Yocom ◽

Jacob Sifers ◽

Henry Uradu ◽

Robin L. Cooper

Keyword(s):

Cold Stress ◽

Room Temperature ◽

Drosophila Larva

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Release of a single neurotransmitter from an identified interneuron coherently affects motor output on multiple time scales

Journal of Neurophysiology ◽

10.1152/jn.01079.2012 ◽

2013 ◽

Vol 109 (9) ◽

pp. 2327-2334 ◽

Cited By ~ 4

Author(s):

Andrew M. Dacks ◽

Klaudiusz R. Weiss

Keyword(s):

Time Scales ◽

Motor Program ◽

Gaba Release ◽

Motor Output ◽

Multiple Time Scales ◽

Multiple Time ◽

Intrinsic Properties ◽

Buccal Ganglion ◽

Motor Programs ◽

Pattern Characteristic

Neurotransmitters can have diverse effects that occur over multiple time scales often making the consequences of neurotransmission difficult to predict. To explore the consequences of this diversity, we used the buccal ganglion of Aplysia to examine the effects of GABA release by a single interneuron, B40, on the intrinsic properties and motor output of the radula closure neuron B8. B40 induces a picrotoxin-sensitive fast IPSP lasting milliseconds in B8 and a slow EPSP lasting seconds. We found that the excitatory effects of this slow EPSP are also mediated by GABA. Together, these two GABAergic actions structure B8 firing in a pattern characteristic of ingestive programs. Furthermore, we found that repeated B40 stimulation induces a persistent increase in B8 excitability that was occluded in the presence of the GABA B receptor agonist baclofen, suggesting that GABA affects B8 excitability over multiple time scales. The phasing of B8 activity during the feeding motor programs determines the nature of the behavior elicited during that motor program. The persistent increase in B8 excitability induced by B40 biased the activity of B8 during feeding motor programs causing the motor programs to become more ingestive in nature. Thus, a single transmitter released from a single interneuron can have consequences for motor output that are expressed over multiple time scales. Importantly, despite the differences in their signs and temporal characteristics, the three actions of B40 are coherent in that they promote B8 firing patterns that are characteristic of ingestive motor outputs.

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A Novel Neuronal Pathway for Visually Guided Escape in Drosophila melanogaster

Journal of Neurophysiology ◽

10.1152/jn.00073.2009 ◽

2009 ◽

Vol 102 (2) ◽

pp. 875-885 ◽

Cited By ~ 59

Author(s):

Haleh Fotowat ◽

Amir Fayyazuddin ◽

Hugo J. Bellen ◽

Fabrizio Gabbiani

Keyword(s):

Drosophila Melanogaster ◽

Activity Pattern ◽

Escape Response ◽

Angular Size ◽

The Novel ◽

Visually Guided ◽

Motor Sequence ◽

Motor Programs ◽

Sensory Activity ◽

Descending Interneurons

Drosophila melanogaster exhibits a robust escape response to objects approaching on a collision course. Although a pair of large command interneurons called the giant fibers (GFs) have been postulated to trigger such behaviors, their role has not been directly demonstrated. Here, we show that escape from visual stimuli like those generated by approaching predators does not rely on the activation of the GFs and consists of a more complex and less stereotyped motor sequence than that evoked by the GFs. Instead, the timing of escape is tightly correlated with the activity of previously undescribed descending interneurons that signal a threshold angular size of the approaching object. The activity pattern of these interneurons shares features with those of visual escape circuits of several species, including pigeons, frogs, and locusts, and may therefore have evolved under similar constraints. These results show that visually evoked escapes in Drosophila can rely on at least two descending neuronal pathways: the GFs and the novel pathway we characterize electrophysiologically. These pathways exhibit very different patterns of sensory activity and are associated with two distinct motor programs.

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Motor Programs as Indicators of Penalty Direction in Soccer

International Journal for Innovation Education and Research ◽

10.31686/ijier.vol8.iss9.2619 ◽

2020 ◽

Vol 8 (9) ◽

pp. 224-233

Author(s):

Luiz Felipe Pinto Oliveira da Motta ◽

Ricardo Fontes Macedo ◽

Elizabeth Cárpio Rivera ◽

Angela Luciana De-Bortoli ◽

Robelius De-Bortoli

Keyword(s):

Behavior Pattern ◽

Video Camera ◽

The Body ◽

Motor Patterns ◽

Motor Programs ◽

Front View ◽

Elbow Angle ◽

Patterns Of Behavior ◽

Prior Intention ◽

Leg Position

Introduction: Many football games are decided on penalties and usually in championship final games. When seeking to anticipate movements, differences in amplitude can harm players because the informational movement appears to be spread "globally" throughout the action and should be coded at several levels. Thus, it would be interesting to analyze the entire period of the kick, since the player begins his run to approach the ball to recognize the motor patterns used in the kick that identify his direction. Objective: The objective of this study is to identify patterns of behavior in penalty kicks that may indicate the direction of their action / kick and in my moment they appear. Methodology: The sample consisted of 21 subjects hitting a penalty kick, 18 males and 3 females with an average age of 22.18 ± 2.44 years and two goalkeepers with college football experience. The tests consisted of a battery of two penalty kicks for each subject in order to score. The kicks were recorded by a video camera with a front view of the goal goal and the back of the batter. The kick phases were divided into the starting leg position; first step leg; angle of the elbow in relation to the body seen from behind; angle of the elbow in relation to the displacement line seen from above; direction of the tip of the supporting foot and position on the goal where the kick was. Each kick was preceded by a start signal. The data were analyzed from the registration of each variable and the position of the goal in which the ball was kicked, considering it in three sectors: left, right and central. Results: The main results indicated that the variable “Leg of the first step” had 81% of the kicks associated with the direction of the goal; 52.4% of second kicks had repeated the pattern of behavior and 84.6% had repeated the pattern of behavior regardless of the goal position. The variable “Elbow angle in relation to the body seen from behind” had 81.8% repeated behavior pattern regardless of the goal position and the variable “Elbow angle in relation to the displacement line seen from above” had 81% association with the sector of the goal in which the ball was kicked; 52.4% of second kicks had repeated the pattern of behavior and 91.7% had repeated the pattern of behavior regardless of the goal position. Conclusions: The main conclusions indicate that it is possible to relate the kick location with the batter's body information; the start of the race seems to indicate that there is a prior intention of movement programs; the decision of where to hit the penalty appears to be made before contact with the ball and more closely to the placement of the support foot and with this relationship, the size of the goal to be defended by the goalkeeper could be reduced, increasing the possibility of defense.

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