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Social and Behavioral Sciences Commons™
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Articles 1 - 5 of 5
Full-Text Articles in Social and Behavioral Sciences
Superior Colliculus Lesions Lead To Disrupted Responses To Light In Diurnal Grass Rats (Arvicanthis Niloticus), Andrew J. Gall, Alyssa M. Goodwin, Ohanes S. Khacherian, Laura B. Teal
Superior Colliculus Lesions Lead To Disrupted Responses To Light In Diurnal Grass Rats (Arvicanthis Niloticus), Andrew J. Gall, Alyssa M. Goodwin, Ohanes S. Khacherian, Laura B. Teal
Faculty Publications
The circadian system regulates daily rhythms of physiology and behavior. Although extraordinary advances have been made to elucidate the brain mechanisms underlying the circadian system in nocturnal species, less is known in diurnal species. Recent studies have shown that retinorecipient brain areas such as the intergeniculate leaflet (IGL) and olivary pretectal nucleus (OPT) are critical for the display of normal patterns of daily activity in diurnal grass rats (Arvicanthis niloticus). Specifically, grass rats with IGL and OPT lesions respond to light in similar ways to intact nocturnal animals. Importantly, both the IGL and OPT project to one another …
Functional And Anatomical Variations In Retinorecipient Brain Areas In Arvicanthis Niloticus And Rattus Norvegicus: Implications For The Circadian And Masking Systems, Dorela D. Shuboni-Mulligan, Breyanna L. Cavanaugh, Anne Tonson, Erik M. Shapiro, Andrew J. Gall
Functional And Anatomical Variations In Retinorecipient Brain Areas In Arvicanthis Niloticus And Rattus Norvegicus: Implications For The Circadian And Masking Systems, Dorela D. Shuboni-Mulligan, Breyanna L. Cavanaugh, Anne Tonson, Erik M. Shapiro, Andrew J. Gall
Faculty Publications
Daily rhythms in light exposure influence the expression of behavior by entraining circadian rhythms and through its acute effects on behavior (i.e., masking). Importantly, these effects of light are dependent on the temporal niche of the organism; for diurnal organisms, light increases activity, whereas for nocturnal organisms, the opposite is true. Here we examined the functional and morphological differences between diurnal and nocturnal rodents in retinorecipient brain regions using Nile grass rats (Arvicanthis niloticus) and Sprague-Dawley (SD) rats (Rattus norvegicus), respectively. We established the presence of circadian rhythmicity in cFOS activation in retinorecipient brain regions in …
Normal Behavioral Responses To Light And Darkness And The Pupillary Light Reflex Are Dependent Upon The Olivary Pretectal Nucleus In The Diurnal Nile Grass Rat, Andrew J. Gall, Ohanes S. Khacherian, Brandi Ledbetter, Sean P. Deats, Megan Luck, Laura Smale, Lily Yan, Antonio A. Nunez
Normal Behavioral Responses To Light And Darkness And The Pupillary Light Reflex Are Dependent Upon The Olivary Pretectal Nucleus In The Diurnal Nile Grass Rat, Andrew J. Gall, Ohanes S. Khacherian, Brandi Ledbetter, Sean P. Deats, Megan Luck, Laura Smale, Lily Yan, Antonio A. Nunez
Faculty Publications
The olivary pretectal nucleus (OPT) is a midbrain structure that receives reciprocal bilateral retinal projections, is involved in the pupillary light reflex, and connects reciprocally with the intergeniculate leaflet (IGL), a retinorecipient brain region that mediates behavioral responses to light pulses (i.e., masking) in diurnal Nile grass rats. Here, we lesioned the OPT and evaluated behavioral responses in grass rats to various lighting conditions, as well as their anxiety-like responses to light exposure. While control grass rats remained diurnal, grass rats with OPT lesions exhibited a more night-active pattern under 12h:12h light-dark (LD) conditions. However, when placed in constant darkness, …
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. …
Intergeniculate Leaflet Lesions Result In Differential Activation Of Brain Regions Following The Presentation Of Photic Stimuli In Nile Grass Rats, Andrew J. Gall, Lily Yan, Laura Smale, Antonio A. Nunez
Intergeniculate Leaflet Lesions Result In Differential Activation Of Brain Regions Following The Presentation Of Photic Stimuli In Nile Grass Rats, Andrew J. Gall, Lily Yan, Laura Smale, Antonio A. Nunez
Faculty Publications
The intergeniculate leaflet (IGL) plays an important role in the entrainment of circadian rhythms and the mediation of acute behavioral responses to light (i.e., masking). Recently, we reported that IGL lesions in diurnal grass rats result in a reversal in masking responses to light as compared to controls. Here, we used Fos as a marker of neural activation to examine the mechanisms by which the IGL may influence this masking effect of light in grass rats. Specifically, we examined the patterns of Fos activation in retinorecipient areas and in brain regions that receive IGL inputs following 1-h light pulses given …