Multiple areas within the reticular activating system (RAS) can hasten awakening from sleep or light planes of anesthesia. However, stimulation in individual sites has shown limited recovery from deep global suppression of brain activity, such as coma. Here we identify a subset of RAS neurons within the anterior portion of nucleus gigantocellularis (aNGC) capable of producing a high degree of awakening represented by a broad high frequency cortical reactivation associated with organized movements and behavioral reactivity to the environment from two different models of deep pharmacologically-induced coma (PIC): isoflurane (1.25%–1.5%) and induced hypoglycemic coma. Activating aNGC neurons triggered awakening by recruiting cholinergic, noradrenergic, and glutamatergic arousal pathways. In summary, we identify an evolutionarily conserved population of RAS neurons, which broadly restore cerebral cortical activation and motor behavior in rodents through the coordinated activation of multiple arousal-promoting circuits.

The righting reflex (RR) is frequently used to assess level of arousal and applied to animal models of a range of neurological disorders. RR produces a binary result that, when positive, is used to infer restoration of consciousness, often without further behavioral corroboration. We find that RR is an unreliable metric for arousal/recovery of consciousness. Instead, cortical activity and motor behavior that accompany RR are a non-binary, superior criterion that accurately calibrates and establishes level of arousal in rodents.

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Syntactic tracking aims to classify a target's spatiotemporal trajectory by using natural language processing models. This paper proposes constrained stochastic context free grammar (CSCFG) models for target trajectories confined to a roadmap. We present a particle filtering algorithm that exploits the CSCFG model structure to estimate the target's trajectory. This metalevel algorithm operates in conjunction with a base-level target tracking algorithm. Extensive numerical results using simulated ground moving target indicator (GMTI) radar measurements show useful improvement in both trajectory classification and target state (both coordinates and velocity) estimation.Keywords-syntactic tracking, constrained stochastic context free grammar (CSCFG), particle filter, Earley Stolcke parser 1 Traditionally, given track information, a radar (human) operator examines target trajectories to determine anomalous behavior. This paper develops natural language models and meta-level signal processing algorithms for estimating anomalous trajectories. Such "middleware" forms the interface between the physical signal processing layer and the radar operator; see also [7] for alternative models for intent using bridging distributions.

31Background: Recovery to a conscious state when emerging from anesthesia requires 32 full cortical desynchronization, initiation of movement and behavioral reactivity to 33 sensory stimuli. However, the variety of cortical electroencephalogram (EEG) patterns 34 associated with specific anesthetics and the paucity of behavioral descriptions during 35 emergence from anesthesia have prevented EEG and behavior as feasible tracking 36 methods to assess emerging from anesthesia. We propose a detailed combined 37 analysis of motor and cortical activity to determine levels of arousal in rodents. 39Methods: Using decreasing anesthetic concentrations, we simultaneously recorded 40 local field potentials (LFPs) and movement in mice. We delineated cortical dynamics 41 and sub-states during emergence from anesthesia by applying a smoothed-Z score to 42 extract dominant frequencies from spectrogram. Then, we implemented KMeans to 43 obtain cortical sub-states. Finally, we used density estimation and an abrupt change 44 detection algorithm to segment cortical activity into periods. We used cortical sub-states 45 obtained during isoflurane traces to supervise sub-states in sevoflurane and a 46 pharmacologically induced-arousal model. This information together with examining 47 videos were used to categorize behavior. 49Results: We identified five cortical periods with restored motor behavior during 50 emergence from isoflurane anesthetic. Periods of structured sub-states denoted when 51 specific motor behaviors occurred. No significant differences were found when 52 comparing the combined cortical features and motor behavior using isoflurane, 53 3 sevoflurane and our arousal-rodent model. We describe graded regimens of cortico-54 motor activity during emergence from anesthesia to assess arousal levels. 55 56 Conclusion: We show cortical patterns denote gradual motor behaviors when emerging 57 from anesthesia. Restoring motor behavior is a dynamic process that begins tens of 58 minutes earlier than the righting reflex. Combining cortical activity and motor behavior 59 unveils novel biomarkers to accurately track emerging from general anesthesia in 60 rodents and likely other species. 61 62 Key words: Emergence from anesthesia, movement, behavioral arousal, cortical 63 biomarkers, cortical periods, spectral analysis, smoothed Z score algorithm, k-means 64 classifier, righting reflex 65 66 67 68 69 70 71 72 4Introduction: 73 Recovery to a conscious state in humans usually comprises full cortical 74 desynchronization, initiation of movement and behavioral reactivity to sensory stimuli 1 . 75 However, the combination of these parameters in rodents is rarely used when assessing 76 arousal when emerging from anesthesia 2 or when investigating the neuronal pathways 77 underlying reversing anesthetic states in animal models 3-6 . A clear discrepancy arises 78 when analyzing cortical activity 7 and behavior among anesthetics. Some data suggests 79 excluding these parameters. For example, the onset of movement during the emergence 8...

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