Dynamic Synaptic Arrangement in Sensory-Motor Pathways of the Adult Locust Flight System

1997 ◽  
Vol 84 (6) ◽  
pp. 234-237 ◽  
Author(s):  
Harald Wolf ◽  
Ansgar Büschges
Keyword(s):  
Flight System ◽  
Motor Pathways ◽  
Locust Flight ◽  
Sensory Motor ◽  
Adult Locust

Plasticity of Synaptic Connections in Sensory-Motor Pathways of the Adult Locust Flight System

1997 ◽  
Vol 78 (3) ◽  
pp. 1276-1284 ◽  
Author(s):  
Harald Wolf ◽  
Ansgar Büschges
Keyword(s):  
Electric Stimulation ◽  
Motor Pattern ◽  
Competitive Interactions ◽  
Synaptic Connections ◽  
Flight System ◽  
Motor Pathways ◽  
Synaptic Contacts ◽  
Locust Flight ◽  
Sensory Motor ◽  
Adult Locust

Wolf, Harald and Ansgar Büschges. Plasticity of synaptic connections in sensory-motor pathways of the adult locust flight system. J. Neurophysiol. 78: 1276–1284, 1997. We investigated possible roles of retrograde signals and competitive interactions in the lesion-induced reorganization of synaptic contacts in the locust CNS. Neuronal plasticity is elicited in the adult flight system by removal of afferents from the tegula, a mechanoreceptor organ at the base of the wing. We severed one hindwing organ and studied the resulting rearrangement of synaptic contacts between flight interneurons and afferent neurons from the remaining three tegulae (2 forewing, 1 hindwing). This was done by electric stimulation of afferents and intracellular recording from interneurons (and occasionally motoneurons). Two to three weeks after unilateral tegula lesion, connections between tegula afferents and flight interneurons were altered in the following way. 1) Axons from the forewing tegula on the operated side had established new synaptic contacts with metathoracic elevator interneurons. In addition, the amplitude of compound excitatory postsynaptic potentials elicited by electric stimulation was increased, indicating that a larger number of afferents connected to any given interneuron. 2) On the side contralateral to the lesion, connectivity between axons from the forewing tegula and elevator interneurons was decreased. 3) The efficacy of the (remaining) hindwing afferents appeared to be increased with regard to both synaptic transmission to interneurons and impact on flight motor pattern. 4) Flight motoneurons, which are normally restricted to the ipsilateral hemiganglion, sprouted across the ganglion midline after unilateral tegula removal and apparently established new synaptic contacts with tegula afferents on that side. The changes on the operated side are interpreted as occupation of synaptic space vacated on the interneurons by the severed hindwing afferents. On the contralateral side, the changes in synaptic contact must be elicited by retrograde signals from bilaterally arborizing flight interneurons, because tegula projections remain strictly ipsilateral. The pattern of changes suggests competitive interactions between forewing and hindwing afferents. The present investigation thus presents evidence that the CNS of the mature locust is capable of extensive synaptic rearrangement in response to injury and indicates for the first time the action of retrograde signals from interneurons.

Recovery of the flight system following ablation of the tegulae in immature adult locusts

1996 ◽  
Vol 199 (6) ◽  
pp. 1395-1403 ◽  
Author(s):  
C Gee ◽  
R Robertson
Keyword(s):  
Locusta Migratoria ◽  
Motor Pattern ◽  
Recovery Period ◽  
Wingbeat Frequency ◽  
Mature Adult ◽  
Flight System ◽  
Mature Adults ◽  
Locust Flight ◽  
Adult Locust ◽  
The Individual

The capacity of the flight system to recover from ablation of the tegulae was studied in immature adult Locusta migratoria and compared with recovery in mature adults. We ablated the hindwing tegulae or all tegulae in adult locusts either 1 day after the imaginal moult (immature locusts) or 2 weeks after the imaginal moult (mature locusts). We monitored recovery throughout the recovery period by using a stroboscope to measure the wingbeat frequency of tethered locusts. In addition, we measured other parameters of the flight motor pattern using electromyographic electrodes implanted into recovered locusts. Both methods of monitoring recovery yielded the same results. There was no reduction, during adult maturation, in the capacity of the locust flight system to recover from the loss of these proprioceptors. Plasticity of the locust flight system was therefore maintained in the mature adult locust. This suggests that the flight system is not fixed and simply implemented when the locust reaches adulthood, but that the circuitry can be remodelled throughout the animal's life to produce behaviour adapted to the needs and constraints of the individual.

scholarly journals Multiple Sensory-Motor Pathways Lead to Coordinated Visual Attention

2016 ◽  
Vol 41 ◽  
pp. 5-31 ◽  
Author(s):  
Chen Yu ◽  
Linda B. Smith
Keyword(s):  
Visual Attention ◽  
Motor Pathways ◽  
Sensory Motor

scholarly journals E. coli chemotaxis is information-limited

2021 ◽  
Author(s):  
H.H. Mattingly ◽  
K. Kamino ◽  
B.B. Machta ◽  
T. Emonet
Keyword(s):  
Escherichia Coli ◽  
Information Acquisition ◽  
Environmental Information ◽  
Behavioral Performance ◽  
Theoretical Limit ◽  
Acquisition Rate ◽  
Motor Pathways ◽  
E Coli ◽  
Sensory Motor

AbstractOrganisms must acquire and use environmental information to guide their behaviors. However, it is unclear whether and how information quantitatively limits behavioral performance. Here, we relate information to behavioral performance in Escherichia coli chemotaxis. First, we derive a theoretical limit for the maximum achievable gradient-climbing speed given a cell’s information acquisition rate. Next, we measure cells’ gradient-climbing speeds and the rate of information acquisition by the chemotaxis pathway. We find that E. coli make behavioral decisions with much less than the 1 bit required to determine whether they are swimming up-gradient. However, they use this information efficiently, performing near the theoretical limit. Thus, information can limit organisms’ performance, and sensory-motor pathways may have evolved to efficiently use information from the environment.

Stuttering

1981 ◽  
Vol 24 (1) ◽  
pp. 25-31 ◽  
Author(s):  
Gerald N. Zimmermann ◽  
Anne Smith ◽  
John M. Hanley
Keyword(s):  
Motor Control ◽  
Motor Pathways ◽  
Physiological Variables ◽  
Control Processes ◽  
Sensory Motor ◽  
Muscle Groups ◽  
Similar Motor ◽  
Therapeutic Considerations

Perceptually fluent and disfluent speech reflect a continuum of coordination and can be best understood in terms of similar motor control processes. Speech movements may be considered to result from the interaction of inputs to motoneuron pools which alter the tuning of sensory-motor pathways and triggering inputs to specific muscles and muscle groups. A disorder in coordination may occur when any of these inputs is aberrantly affected by psychological, psychosocial or physiological variables. Specific phenomena associated with stuttering--adaptation, masking, whispering and voicing deviations--are interpreted in terms of these neuromotor processes. Therapeutic considerations are discussed.

Connections of the forewing tegulae in the locust flight system and their modification following partial deafferentation

1992 ◽  
Vol 23 (1) ◽  
pp. 44-60 ◽  
Author(s):  
Ansgar Büschges ◽  
Jan-Marino Ramirez ◽  
Robert Driesang ◽  
Keir G. Pearson
Keyword(s):  
Flight System ◽  
Locust Flight
Sign in / Sign up

Export Citation Format

Share Document