Abstract:
During developmental critical periods (CPs), early-life stress (ELS) induces cognitive deficits and alters neural circuitry in regions underlying learning, memory, and attention. Mechanisms underlying critical period plasticity are shared by sensory cortices and these higher neural regions, suggesting that sensory processing may also be vulnerable to ELS. In particular, the perception and auditory cortical (ACx) encoding of temporally-varying sounds both mature gradually, even into adolescence, providing an extended postnatal window of susceptibility. To examine the effects of ELS on temporal processing, we developed a model of ELS in the Mongolian gerbil, a well-established model for auditory processing. In both male and female animals, ELS induction impaired the behavioral detection of short gaps in sound, which are critical for speech perception. This was accompanied by reduced neural responses to gaps in auditory cortex, the auditory periphery, and auditory brainstem. ELS thus degrades the fidelity of sensory representations available to higher regions, and could contribute to well-known ELS-induced problems with cognition.SIGNIFICANCE STATEMENT In children and animal models, early-life stress (ELS) leads to deficits in cognition, including problems with learning, memory, and attention. Such problems could arise in part from a low-fidelity representation of sensory information available to higher-level neural regions. Here, we demonstrate that ELS degrades sensory responses to rapid variations in sound at multiple levels of the auditory pathway, and concurrently impairs perception of these rapidly-varying sounds. As these sound variations are intrinsic to speech, ELS may thus pose a challenge to communication and cognition through impaired sensory encoding.
摘要:
在发育关键时期,早期生活压力(ELS)引起认知缺陷并改变潜在学习区域的神经回路,记忆,和注意。关键时期可塑性的潜在机制由感觉皮质和这些较高的神经区域共享,这表明感官加工也可能容易受到ELS的影响。特别是,时变声音的感知和听觉皮层编码都逐渐成熟,甚至进入青春期,提供了一个延长的产后易感性窗口。为了检查ELS对时间处理的影响,我们在蒙古沙鼠中开发了ELS模型,一个完善的听觉处理模型。在雄性和雌性动物中,ELS感应损害了声音中短间隙的行为检测,这对言语感知至关重要。这伴随着对听觉皮层间隙的神经反应减少,听觉外围,和听觉脑干。因此,ELS降低了较高区域可用的感觉表征的保真度,并可能导致众所周知的ELS引起的认知问题。重要性声明:在儿童和动物模型中,早期生活压力(ELS)导致认知缺陷,包括学习问题,记忆,和注意。这些问题可能部分是由于高级神经区域可用的感觉信息的低保真度表示引起的。在这里,我们证明了ELS在听觉通路的多个层面上降低了对声音快速变化的感觉反应,同时削弱了对这些快速变化的声音的感知。由于这些声音变化是语音固有的,因此,ELS可能通过受损的感觉编码对交流和认知构成挑战。