In this context, SD affords an additional unique window to examine how brain states affect sensory processing by offering a ‘middle-tier’ alternative - a state where subjects are awake and responsive but already show behavioral deficits ( Krause et al., 2017 Lim and Dinges, 2010).
The third strategy contrasts sensory processing in wakefulness with those during anesthesia or natural sleep ( Bergman et al., 2022 Issa and Wang, 2011, 2013 Krom et al., 2020 Nir et al., 2013a Nourski et al., 2018 Raz et al., 2014 Sela et al., 2020). A second approach focuses on momentary changes in arousal, indexed by pupil size, EEG or locomotor activity during wakefulness ( Bereshpolova et al., 2011 Lin et al., 2019 McGinley et al., 2015 Zhou et al., 2014 Zhuang et al., 2014). Such studies typically employ one of the following three strategies One approach is studying how sensory processing differs with respect to behavioral performance on specific tasks ( Atiani et al., 2009, 2014 Jaramillo and Zador, 2011 Kato et al., 2015 Otazu et al., 2009). A rich body of literature reports the effects of behavioral state and arousal on sensory processing, particularly in the auditory domain. Studying the effects of SD on early sensory processing can help shed light on the fundamental processes by which the slow buildup of sleep pressure alters neural processing.Ī parallel, equally important, motivation for studying the effects of SD on sensory processing is that it serves as a unique and powerful model for assessing the effects of brain state and arousal on sensory processing at the neuronal level ( Harris and Thiele, 2011 Lee and Dan, 2012). However, it remains largely unknown whether such effects are restricted to high-order multi-modal regions, or may also affect neuronal activities along specific sensory pathways. One study examined the effects of extended wakefulness on sensory responses in high-order human temporal lobe neurons, reporting attenuated, prolonged and delayed responses associated with behavioral lapses ( Nir et al., 2017). In the rat frontal cortex, robust changes in spontaneous cortical activity gradually emerge during merely a few hours of SD ( Vyazovskiy et al., 2011). Previous non-invasive studies examined the effect of insufficient sleep on neurophysiological activity ( Basner et al., 2013 Chee, 2015 Finelli et al., 2000 Krause et al., 2017 Lorenzo et al., 1995), yet only few studies examined the effects of SD on spiking activities in local neuronal populations. Cognitive functions particularly affected by SD include psychomotor and cognitive speed, vigilant and executive attention, working memory, emotional regulation, and higher cognitive abilities ( Krause et al., 2017) associated with activity in attentional thalamic and fronto-parietal circuits ( Chee et al., 2008 Drummond et al., 1999, 2005 Padilla et al., 2006 Portas et al., 1998 Thomas et al., 2000 Tomasi et al., 2009 Weissman et al., 2006 Wu et al., 2006). During SD, homeostatic and circadian processes interact to build up sleep pressure ( Borbély, 1982) that impairs cognitive performance ( Doran et al., 2001), and can lead to serious consequences such as car accidents and medical errors ( Carskadon, 2004). Sleep deprivation (SD) is inherent to modern daily life and entails considerable social and health-related costs ( Carskadon, 2004). Our results show that processes akin to those in NREM sleep invade the activity of cortical circuits during SD, already in early sensory cortex. Recovery NREM sleep was associated with similar effects as SD with even greater magnitude, while auditory processing during REM sleep was similar to vigilant wakefulness. By contrast, SD decreased entrainment to rapid (≥20 Hz) click-trains, increased population synchrony, and increased the prevalence of sleep-like stimulus-induced silent periods, even when ongoing activity was similar.
We found that frequency tuning, onset responses, and spontaneous firing rates were largely unaffected by SD. Here, we recorded spiking activity in rat auditory cortex along with polysomnography while presenting sounds during SD followed by recovery sleep. Specifically, which aspects of cortical processing are affected by sleep deprivation (SD), and whether they also affect early sensory regions, remains unclear. Insufficient sleep is commonplace in modern lifestyle and can lead to grave outcomes, yet the changes in neuronal activity accumulating over hours of extended wakefulness remain poorly understood.
0 kommentar(er)
