JN-00625-2006.R1, accepted Load signals assist the generation of movement dependent reflex reversal in the femur-tibia joint of stick insects
نویسندگان
چکیده
Reinforcement of movement is an important mechanism by which sensory feedback contributes to motor control for walking. We investigate how sensory signals from movement and load sensors interact in controlling the motor output of the stick insect femur-tibia (FT-) joint. In stick insects, flexion signals from the femoral chordotonal organ (fCO) at the FTjoint and load signals from the femoral campaniform sensilla (fCS) are known to individually reinforce stance phase motor output of the FT-joint by promoting flexor and inhibiting extensor motoneuron activity. We quantitatively compared the time course of inactivation in extensor tibiae motoneurons in response to selective stimulation of fCS and fCO. Stimulation of either sensor effects extensor activity in a qualitatively similar manner but with a significantly different time course and frequency of occurrence. Inactivation of extensor motoneurons due to fCS stimulation was more reliable but more than three-fold slower as compared to the extensor inactivation in response to flexion signals from the fCO. In contrast, simultaneous stimulation of both sense organs produced inactivation in motoneurons with a time course typical for fCO stimulation alone, but with a frequency of occurrence characteristic for fCS stimulation. This increase in probability of occurrence was also accompanied by a delayed re-activation of the extensor motoneurons. Our results indicate for the first time that fCS load signals from the leg affect the processing of movement related feedback from the fCO in controlling motor output. Page 2 of 22
منابع مشابه
Load signals assist the generation of movement-dependent reflex reversal in the femur-tibia joint of stick insects.
Reinforcement of movement is an important mechanism by which sensory feedback contributes to motor control for walking. We investigate how sensory signals from movement and load sensors interact in controlling the motor output of the stick insect femur-tibia (FT) joint. In stick insects, flexion signals from the femoral chordotonal organ (fCO) at the FT joint and load signals from the femoral c...
متن کاملRole of proprioceptive signals from an insect femur-tibia joint in patterning motoneuronal activity of an adjacent leg joint.
Interjoint reflex function of the insect leg contributes to postural control at rest or to movement control during locomotor movements. In the stick insect (Carausius morosus), we investigated the role that sensory signals from the femoral chordotonal organ (fCO), the transducer of the femur-tibia (FT) joint, play in patterning motoneuronal activity in the adjacent coxa-trochanteral (CT) joint ...
متن کاملPremotor interneurons in the local control of stepping motor output for the stick insect single middle leg.
In insect walking systems, nonspiking interneurons (NSIs) play an important role in the control of posture and movement. As such NSIs are known to contribute to state-dependent modifications in processing of proprioceptive signals from the legs. For example, NSIs process a flexion of the femur-tibia (FTi) joint signaled by the femoral chordotonal organ (fCO) such that the stance phase motor out...
متن کاملA neuromechanical model for the neuronal basis of curve walking in the stick insect.
The coordination of the movement of single and multiple limbs is essential for the generation of locomotion. Movement about single joints and the resulting stepping patterns are usually generated by the activity of antagonistic muscle pairs. In the stick insect, the three major muscle pairs of a leg are the protractor and retractor coxae, the levator and depressor trochanteris, and the flexor a...
متن کاملControl of reflex reversal in stick insect walking: effects of intersegmental signals, changes in direction, and optomotor-induced turning.
In many animals, the effects of sensory feedback on motor output change during locomotion. These changes can occur as reflex reversals in which sense organs that activate muscles to counter perturbations in posture control instead reinforce movements in walking. The mechanisms underlying these changes are only partially understood. As such, it is unclear whether reflex reversals are modulated w...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2006