Learn More
Timing of the repetitive movements that constitute any rhythmic behavior is regulated by intrinsic properties of the central nervous system rather than by sensory feedback from moving parts of the body. Evidence of this permits resolution of the long-standing controversy over the neural basis of rhythmic behavior and aids in the identification of this(More)
This paper describes a six-legged robot based on the features of an agile insect, the American cockroach, Periplaneta americana. The robot is designed with insect-like leg structure and placement, and actuators that mimic muscles. A test leg is also described that shows how sensory feedback can serve as the basis of the control system for the robot in order(More)
1. The mechanoreceptive campaniform sensilla, which are arranged in groups on insect legs, were studied in the stick insect Cuniculina impigra. In middle and rear legs, the most posterior trochanteral campaniform group (group 1) is oriented so as to be stimulated by compressional cuticular forces acting on the posterior articulation of the trochanter with(More)
1. The effects of amputation of a middle leg on the motor pattern in the legs of freely walking cockroaches (Periplaneta americana L.) were studied. 2. The general effects of amputating a middle leg are similar to those arising from amputation of a rear leg. These effects are: multiple bursting, more variable and inconsistent timing (phase) between bursts(More)
A computer algorithm to identify 'bursts' in trains of spikes is described. The algorithm works by constructing a histogram of interspike intervals, then analyzing the histogram to detect the critical interval value in the distribution that represents the break between short intervals within a burst and the longer intervals between bursts. When such a value(More)
1. Rhythmic motor activity may be recorded in the legs of cockroaches during the execution of several different types of behaviour that involve leg movements. It was examined in detail during searching and walking. 2. During walking, motor activity always consisted of a series of bursts separated by silent periods. During searching, it was usually(More)
1. The effects of amputation of a rear leg on the pattern of motor activity in the legs of freely walking cockroaches (Periplaneta americana L.) were studied. 2. Amputation affected both the frequency and the timing (phase) of motor bursts during a stepping cycle. Bursts in the stump of an amputated rear leg and in the contralateral (intact) rear leg often(More)
A spike discrimination algorithm based on the analysis of spike up- and down-slopes can advantageously replace those based only on amplitude with a minimal increase of programming complexity and processing time. Such an algorithm was developed to sort muscle depolarizations from nerve spikes in electromyograms in insects. It could also be used to sort(More)
Campaniform sensilla (cs) on insect legs are stimulated by strain in the cuticle produced by forces applied to the leg, and generate action potentials when the strain is sufficiently high. We modeled the tibia of the American cockroach, Periplaneta americana, as a hollow, circular tube and developed a simulation of cs responses to external forces by solving(More)