Figure 7. Examples of disynaptic IPSPs evoked from both ipsilateral and contralateral group II muscle afferents in a commissural interneurone that was monosynaptically excited from the MLF.

Upper traces in all panels are intracellular records; lower traces are records from the cord dorsum. A, EPSPs evoked from MLF, classified as comprising an early monosynaptic component (segmental latency 0.65 ms) and a later disynaptic component. The earliest parts of the temporally facilitated disynaptic components were superimposed on the monosynaptic EPSPs. B and C, disynaptic IPSPs evoked from ipsilateral and contralateral group II afferents, at latencies 2.8 and 3.1 ms with respect to group I afferent volleys evoked by the second stimulus. At the extreme right hand side of the records in C is a blocked spike evoked by a stimulus delivered to the contralateral GS motor nuclei (50 μA). Dotted lines indicate the onset of the volleys and the EPSPs or IPSPs following these volleys.