Synaptic timing between excitation and inhibition sets each inferior-colliculus neuron’s preferred modulation frequency

Evidence

The band-enhanced model (Fig. 1 , BE) was Nelson and Carney’s ( 2004 ) same-frequency inhibitory-excitatory (SFIE) model. The key mechanism in this model is a dynamic interaction between relatively short-duration excitatory and relatively long-duration, delayed inhibitory synaptic potentials. The durations of the excitatory and inhibitory potentials and the delay of the inhibition with respect to the excitation determine the model’s best modulation frequency (BMF). An extension of the SFIE model was used for the band-suppressed model (Fig. 1 , BS). This model receives the same ascending excitatory input as the band-enhanced model, but it is inhibited by the band-enhanced model (Carney et al. 2015 ; Kim et al. 2015b ). The BMF of the band-enhanced model determines the worst modulation frequency (WMF) for the band-suppressed model. Finally, the hybrid MTF model receives the same ascending excitatory input as the other model IC neurons, but is inhibited by both band-enhanced and band-suppressed cells (Fig. 1 , Hybr). The relation between the BMF and WMF of the inhibitory inputs determines the shape of the hybrid model cell’s MTF. — Dijk, Pim van, Physiology, Psychoacoustics and…, 5478

Categorization

Category: Definitional Content

• DEFINE: Explains the SFIE mechanism: how the delay between short excitation and longer delayed inhibition sets a neuron’s best modulation frequency, plus the hierarchical inhibition wiring across the three MTF types.
• XREF: Connects to computing/neural-network notions of temporal integration: a neuron’s selectivity emerges from excitation-inhibition timing asymmetries rather than static tuning.

Related

• Inhibitory-excitatory synaptic timing determines a midbrain neuron’s best modulation frequency. (similarity 0.92)
• Cellular synaptic timing parameters determine a neuron’s preferred modulation frequency (similarity 0.89)
• Inferior colliculus neurons show only three types of modulation tuning that can be modeled (similarity 0.85)
• The band-enhanced neuron’s timing constrains the band-suppressed neuron’s tuning (similarity 0.83)
• Two inhibitory inputs jointly shape the hybrid neuron’s modulation response (similarity 0.83)
• Band-suppressed IC cells derive their suppression from band-enhanced cell inhibition (similarity 0.80)