<P> The lamprey has been used as a model for vertebrate CPGs because , while its nervous system has a vertebrate organization , it shares many positive characteristics with invertebrates . When removed from the lamprey , the intact spinal cord can survive for days in vitro . It also has very few neurons and can be easily stimulated to produce a fictive swimming motion indicative of a central pattern generator . As early as 1983 , Ayers , Carpenter , Currie and Kinch proposed that there was a CPG responsible for most undulating movements in the lamprey including swimming forward and backward , burrowing in the mud and crawling on a solid surface , that although not surprisingly did not match the activity in the intact animal , nevertheless provided the basic locomotor output . The different movements have been found to be altered by neuromodulators , including serotonin in a study by Harris - Warrick and Cohen in 1985 and tachykinin in a study by Parker et al. in 1998 . The lamprey model of CPG for locomotion has been important to the study of CPGs . Although Sten Grillner claims that the locomotor network is characterised , a claim that has seemingly been uncritically accepted by the spinal cord locomotor network field , there are in fact many missing details and Grillner can not provide the evidence he uses to support his claims ( Parker 2006 ) . A general scheme of the lamprey CPG is now being used in the creation of artificial CPGs . For example , Ijspeert and Kodjabachian used Ekeberg 's model for the lamprey to create artificial CPGs and simulate swimming movements in a lamprey - like substrate using controllers based on a SGOCE encoding . Essentially , these are the first steps toward the use of CPGs to code for locomotion in robots . The vertebrate model of CPG has been also developed with both Hodgkin - Huxley formalism , its variants and control system approaches . For example , Yakovenko and colleagues have developed a simple mathematical model that describes basic principles proposed by T.G. Brown with integrate - to - threshold units organized with mutually inhibitory connections . This model is sufficient to describe complex properties of behavior , such as different regimes of the extensor - and flexor - dominant locomotion observed during electrical stimulation of the mesencephalic locomotor region ( MLR ) , MLR - induced fictive locomotion . </P>
<P> The lamprey has been used as a model for vertebrate CPGs because , while its nervous system has a vertebrate organization , it shares many positive characteristics with invertebrates . When removed from the lamprey , the intact spinal cord can survive for days in vitro . It also has very few neurons and can be easily stimulated to produce a fictive swimming motion indicative of a central pattern generator . As early as 1983 , Ayers , Carpenter , Currie and Kinch proposed that there was a CPG responsible for most undulating movements in the lamprey including swimming forward and backward , burrowing in the mud and crawling on a solid surface , that although not surprisingly did not match the activity in the intact animal , nevertheless provided the basic locomotor output . The different movements have been found to be altered by neuromodulators , including serotonin in a study by Harris - Warrick and Cohen in 1985 and tachykinin in a study by Parker et al. in 1998 . The lamprey model of CPG for locomotion has been important to the study of CPGs . Although Sten Grillner claims that the locomotor network is characterised , a claim that has seemingly been uncritically accepted by the spinal cord locomotor network field , there are in fact many missing details and Grillner can not provide the evidence he uses to support his claims ( Parker 2006 ) . A general scheme of the lamprey CPG is now being used in the creation of artificial CPGs . For example , Ijspeert and Kodjabachian used Ekeberg 's model for the lamprey to create artificial CPGs and simulate swimming movements in a lamprey - like substrate using controllers based on a SGOCE encoding . Essentially , these are the first steps toward the use of CPGs to code for locomotion in robots . The vertebrate model of CPG has been also developed with both Hodgkin - Huxley formalism , its variants and control system approaches . For example , Yakovenko and colleagues have developed a simple mathematical model that describes basic principles proposed by T.G. Brown with integrate - to - threshold units organized with mutually inhibitory connections . This model is sufficient to describe complex properties of behavior , such as different regimes of the extensor - and flexor - dominant locomotion observed during electrical stimulation of the mesencephalic locomotor region ( MLR ) , MLR - induced fictive locomotion . </P>
proper functioning of the lamprey central pattern generator ( cpg ) is dependent on which input
proper functioning of the lamprey central pattern generator ( cpg ) is dependent on which input
neuromodulators
neuromodulators