Short-term synaptic plasticity and intensity coding

Abstract

Alterations in synaptic strength over short time scales, termed short-term synaptic plasticity, can gate the flow of information through neural circuits. Different information can be extracted from the same presynaptic spike train depending on the activity- and time-dependent properties of the plasticity at a given synapse. The parallel processing in the brain stem auditory pathways provides an excellent model system for investigating the functional implications of short-term plasticity in neural coding. We review recent evidence that short-term plasticity differs in different pathways with a special emphasis on the ‘intensity’ pathway. While short-term depression dominates the ‘timing’ pathway, the intensity pathway is characterized by a balance of short-term depression and facilitation that allows linear transmission of rate-coded intensity information. Target-specific regulation of presynaptic plasticity mechanisms underlies the differential expression of depression and facilitation. The potential contribution of short-term plasticity to different aspects of ‘intensity’-related information processing, such as interaural level/intensity difference coding, amplitude modulation coding, and intensity-dependent gain control coding, is discussed.

Multiplexed temporal coding of electric communication signals in mormyrid fishes

“…Differences in the relative magnitude and time course of depression in excitatory and inhibitory pathways may contribute to interval tuning as well as directional sensitivity to changes in interval. Short-term depression is also prevalent in avian and mammalian auditory timecoding pathways (MacLeod, 2011).…”

“…Differences in the relative magnitude and time course of depression in excitatory and inhibitory pathways may contribute to interval tuning as well as directional sensitivity to changes in interval. Short-term depression is also prevalent in avian and mammalian auditory timecoding pathways (MacLeod, 2011).In addition to synaptic mechanisms, intrinsic membrane properties of postsynaptic neurons can contribute to temporal filtering (Hutcheon and Yarom, 2000;Mehaffey et al, 2008b). First, the membrane itself passively filters high-frequency fluctuations in membrane potential.…”

Short-Term Synaptic Plasticity Regulation in Solution-Gated Indium–Gallium–Zinc-Oxide Electric-Double-Layer Transistors

“…1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 Paired-pulse facilitation (PPF) is an essential short-term plasticity in decoding temporal information in auditory or visual signals. 24,25 The IGZO-based synaptic transistor gated by aqueous solution can also mimic such synaptic function. As shown in Figure 3a, when two successive spikes with a time interval (ΔT) of 40 ms are applied on presynaptic terminal of a DI water gated IGZO-based synaptic transistor, two EPSC peaks are observed.…”

Functional roles of short-term synaptic plasticity with an emphasis on inhibition

“…Although multiple roles for STP have been suggested [18], there is little direct experimental evidence to support a particular function. Similarly, the calyx of the Held synapse in the mammalian auditory system, due to its accessibility and interesting dynamics [19], has been studied extensively for mechanisms of STP.…”