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Full-Text Articles in Psychology
Suprachiasmatic Nucleus And Subparaventricular Zone Lesions Disrupt Circadian Rhythmicity But Not Light-Induced Masking Behavior In Nile Grass Rats, Andrew J. Gall, Dorela D. Shuboni, Lily Yan, Antonio A. Nunez, Laura Smale
Suprachiasmatic Nucleus And Subparaventricular Zone Lesions Disrupt Circadian Rhythmicity But Not Light-Induced Masking Behavior In Nile Grass Rats, Andrew J. Gall, Dorela D. Shuboni, Lily Yan, Antonio A. Nunez, Laura Smale
Faculty Publications
The ventral subparaventricular zone (vSPVZ) receives direct retinal input and influences the daily patterning of activity in rodents, making it a likely candidate for the mediation of acute behavioral responses to light (i.e., masking). We performed chemical lesions aimed at the vSPVZ of diurnal grass rats (Arvicanthis niloticus) using N-methyl-D,L-aspartic acid (NMA), a glutamate agonist. Following NMA lesions, we placed grass rats in various lighting conditions (e.g., 12:12 light-dark, constant dark, constant light); presented a series of light pulses at circadian times (CT) 6, 14, 18, and 22; and placed them in a 7-h ultradian cycle to assess behavioral masking. …
The Development Of Sleep-Wake Rhythms And The Search For Elemental Circuits In The Infant Brain, Mark S. Blumberg, Andrew J. Gall, William D. Todd
The Development Of Sleep-Wake Rhythms And The Search For Elemental Circuits In The Infant Brain, Mark S. Blumberg, Andrew J. Gall, William D. Todd
Faculty Publications
Despite the predominance of sleep in early infancy, developmental science has yet to play a major role in shaping concepts and theories about sleep and its associated ultradian and circadian rhythms. Here we argue that developmental analyses help us to elucidate the relative contributions of the brainstem and forebrain to sleep-wake control and to dissect the neural components of sleep-wake rhythms. Developmental analysis also makes it clear that sleep-wake processes in infants are the foundation for those of adults. For example, the infant brainstem alone contains a fundamental sleep-wake circuit that is sufficient to produce transitions among wakefulness, quiet sleep, …
Distinct Retinohypothalamic Innervation Patterns Predict The Developmental Emergence Of Species-Typical Circadian Phase Preference In Nocturnal Norway Rats And Diurnal Nile Grass Rats, William D. Todd, Andrew J. Gall, Joshua A. Weiner, Mark S. Blumberg
Distinct Retinohypothalamic Innervation Patterns Predict The Developmental Emergence Of Species-Typical Circadian Phase Preference In Nocturnal Norway Rats And Diurnal Nile Grass Rats, William D. Todd, Andrew J. Gall, Joshua A. Weiner, Mark S. Blumberg
Faculty Publications
How does the brain develop differently to support nocturnality in some mammals, but diurnality in others? To answer this question, one might look to the suprachiasmatic nucleus (SCN), which is entrained by light via the retinohypothalamic tract (RHT). However, because the SCN is more active during the day in all mammals studied thus far, it alone cannot determine circadian phase preference. In adult Norway rats (Rattus norvegicus), which are nocturnal, the RHT also projects to the ventral subparaventricular zone (vSPVZ), an adjacent region that expresses an in-phase pattern of SCN-vSPVZ neuronal activity. In contrast, in adult Nile grass rats (Arvicanthis …
The Development Of Day-Night Differences In Sleep And Wakefulness In Norway Rats And The Effect Of Bilateral Enucleation, Andrew J. Gall, William D. Todd, Baisali Ray, Cassandra M. Coleman, Mark S. Blumberg
The Development Of Day-Night Differences In Sleep And Wakefulness In Norway Rats And The Effect Of Bilateral Enucleation, Andrew J. Gall, William D. Todd, Baisali Ray, Cassandra M. Coleman, Mark S. Blumberg
Faculty Publications
The suprachiasmatic nucleus (SCN) exhibits circadian rhythmicity in fetal and infant rats, but little is known about the consequences of this rhythmicity for infant behavior. Here, in Experiment 1, we measured sleep and wakefulness in rats during the day and night in postnatal day (P)2, P8, P15 and P21 subjects. As early as P2, day-night differences in sleep-wake activity were detected. Nocturnal wakefulness began to emerge around P15 and was reliably expressed by P21. We hypothesized that the process of photic entrainment over the first postnatal week, which depends upon the development of connectivity between the retinohypothalamic tract (RHT) and …