Acute and chronic sleep loss produce different exploration patterns

After twelve hours of acute deprivation, mice spend more time in centers and open arms and move more. Differences subside by twenty-four hours, without significant measured fear-extinction changes.

Seven days of partial daily deprivation reduce center/open-arm time and slow freezing decline during extinction. Total movement and shock-response thresholds do not significantly change, motivating investigation of neuropeptide cells.

Original figure 1Behavior after acute and chronic sleep loss

Excitatory responses weaken in PVN oxytocin cells

Chronic deprivation lowers PVN OXT c-Fos and increases mPFC/central-amygdala markers. PVN OXT AMPA-related currents decrease, while NMDA-related currents do not significantly change.

Miniature excitatory-event amplitudes decrease without frequency changes, while inhibitory-event amplitudes/frequencies remain unchanged. The measured alterations concentrate on excitatory synaptic responses.

Original figure 2Activity markers and excitatory currents

Activating the population changes exploration in normal mice

In normal males, immediate PVN OXT optical activation increases center/open-arm time without significantly changing movement distance, altering open-area exploration without a detected general activity increase.

Training freezing does not significantly differ, while activation yields faster decline during extinction. Effects on exploration and extinction motivate examination of downstream connections.

Original figure 3Exploration and extinction in normal mice

Different terminal targets yield different exploration outcomes

PVN OXT cells project to multiple regions. mPFC-terminal activation increases center/open-arm time; SON-terminal activation does not produce equivalent clear changes, distinguishing target-associated effects.

With an OXT-receptor antagonist, exploration changes during mPFC-terminal activation are nonsignificant. OXT sensors detect activation-linked prefrontal signals, connecting terminals, peptide signaling and exploration.

Original figure 4mPFC versus SON terminals

Prolonged low-frequency stimulation leaves weaker synaptic responses

Comparing low-frequency aftereffects in sleep-deprived mice, next-day slices show weaker AMPA-related currents and miniature excitatory-event amplitudes in cells receiving prolonged stimulation. NMDA currents and event frequency do not change significantly. This differs from immediate activation effects and shows that stimulation can leave subsequent changes.

Low-frequency-treated normal mice explore centers/open arms less and freeze more during extinction, without significant movement or training-freezing changes. Effects involve both immediate activity and subsequent synaptic state.

Original figure 5Currents and behavior after low-frequency stimulation

Exploration remains modifiable after heart-rate differences subside

Seven days after deprivation ends, measured heart-rate differences are nonsignificant while exploration/extinction changes remain. Brief high-frequency PVN OXT stimulation increases center/open-arm time and reduces extinction freezing.

Movement, training freezing and pre-extinction baseline freezing remain nonsignificantly changed. Effects concern open-environment choice and extinction responses, motivating tests of synaptic aftereffects.

Original figure 6Model behavior after high-frequency stimulation

PVN excitation and prefrontal inhibition change together

Next-day PVN OXT AMPA currents and miniature excitatory amplitudes increase, without frequency/NMDA changes. Prefrontal recordings show recovery of reduced light-evoked inhibition and inhibitory-event frequency, without significant excitatory-input changes.

After high-frequency treatment, PVN activation evokes larger prefrontal OXT-sensor responses than controls. With receptor antagonism, the exploratory improvement is absent, adding peptide-related signals alongside synaptic and behavioral outcomes.

This male-mouse study links post-sleep-loss behavior with peptide cells and synaptic states. Prolonged low-frequency and brief high-frequency interventions leave distinct aftereffects, showing how pattern and observation time shape circuit outcomes.

Original figure 7Synaptic measures at both sites after high-frequency stimulation