The onset of visual experience gates auditory cortex critical periods

Abstract

Sensory systems influence one another during development and deprivation can lead to cross-modal plasticity. As auditory function begins before vision, we investigate the effect of manipulating visual experience during auditory cortex critical periods (CPs) by assessing the influence of early, normal and delayed eyelid opening on hearing loss-induced changes to membrane and inhibitory synaptic properties. Early eyelid opening closes the auditory cortex CPs precociously and dark rearing prevents this effect. In contrast, delayed eyelid opening extends the auditory cortex CPs by several additional days. The CP for recovery from hearing loss is also closed prematurely by early eyelid opening and extended by delayed eyelid opening. Furthermore, when coupled with transient hearing loss that animals normally fully recover from, very early visual experience leads to inhibitory deficits that persist into adulthood. Finally, we demonstrate a functional projection from the visual to auditory cortex that could mediate these effects.

Dynamic postnatal development of the cellular and circuit properties of striatal D1 and D2 spiny projection neurons

“…In conclusion, we show that early postnatal development of the intrinsic cellular and circuit properties of the D1-expressing direct pathway and the D2-expressing indirect pathway SPNs is highly dynamic but follows a clear developmental trajectory. Moreover, we show that many of the properties of mature D1 and D2 SPNs are already apparent by the first and second postnatal weeks, which is thought to be a period prior to much exploratory motor behaviour (Dehorter et al 2011) or exposure to structured input from the sensory periphery (Tobach et al 1971;Krug et al 2001;Akerman et al 2002;Ko et al 2013;Mowery et al 2015Mowery et al , 2016Mowery et al , 2017. This is consistent with the idea that neuronal specification can occur early in development (Lobo et al 2006(Lobo et al , 2008Arlotta et al 2008;Ehrman et al 2013;Lu et al 2014;Zhang et al 2016;Merchan-Sala et al 2017;Kelly et al 2018;Tinterri et al 2018;Xu et al 2018) with further postnatal development guided by, for example, neural activity (Zhang & Poo, 2001;Kozorovitskiy et al 2012;Peixoto et al 2016) and neuromodulation (Kozorovitskiy et al 2015;Lieberman et al 2018).…”

The Sensory Striatum Is Permanently Impaired by Transient Developmental Deprivation

“…Injections of the anatomical tracer fluororuby (FR) into core ACx (n=8 gerbils, P55–65) were carried out as previously reported (Mowery et al, 2016). …”

“…Earplugging was carried out as previously reported in detail (Mowery et al, 2015; 2016). This manipulation produces a threshold shift of 15–50 dB, depending on frequency, as measured with auditory brainstem responses (Caras and Sanes, 2015), and ~25 dB at 4 kHz as measured behaviorally (Mowery et al, 2015).…”

“…Whole cell current and voltage clamp recordings were carried out and analyzed as reported previously (Mowery et al, 2015; 2016). Excitatory properties were obtained in one of two ways.…”

“…A craniotomy was made in the temporal bone at the level of core ACx and a durotomy was made, as described previously (Mowery et al, 2016). Glass electrodes were loaded with adenovirus containing a CaMKII promotor that infects pyramidal neurons (AAV1.CaMKIIa.hChR2(H134R)- mCherry.WPRE.hGH; Penn Vector core, Addgene26975) and a Nanoject (Drummond) was then used deliver 50 nL of virus at 800 µm from the pial surface.…”