Interaction between neocortical and hippocampal networks via slow oscillations

Abstract Purpose of review This paper reviews all optogenetic studies that directly test various sleep states, traits, and circuit-level activity profiles for the consolidation of different learning tasks. Recent findings Inhibiting or exciting neurons involved either in the production of sleep states or in the encoding and consolidation of memories reveals sleep states and traits that are essential for memory. REM sleep, NREM sleep, and the N2 transition to REM (characterized by sleep spindles) are integral to memory consolidation. Neural activity during sharp-wave ripples, slow oscillations, theta waves, and spindles are the mediators of this process. Summary These studies lend strong support to the hypothesis that sleep is essential to the consolidation of memories from the hippocampus and the consolidation of motor learning which does not necessarily involve the hippocampus. Future research can further probe the types of memory dependent on sleep-related traits and on the neurotransmitters and neuromodulators required.

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Slow oscillations as a probe of the dynamics of the locus coeruleus-frontal cortex interaction in anesthetized rats

Journal of Physiology-Paris ◽

10.1016/s0928-4257(97)82407-2 ◽

1997 ◽

Vol 91 (6) ◽

pp. 273-284 ◽

Cited By ~ 23

Author(s):

R Lestienne ◽

A Hervé-Minvielle ◽

D Robinson ◽

L Briois ◽

SJ Sara

Keyword(s):

Frontal Cortex ◽

Locus Coeruleus ◽

Slow Oscillations ◽

Anesthetized Rats

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Prolonged response of skeletal muscle in the absence of penetrating anions

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1960.198.2.289 ◽

1960 ◽

Vol 198 (2) ◽

pp. 289-299 ◽

Cited By ~ 31

Author(s):

Gertrude Falk ◽

Jorge F. Landa

Keyword(s):

Action Potentials ◽

Critical Concentration ◽

Relaxation Oscillations ◽

Plateau Phase ◽

Slow Oscillations ◽

Mechanical Responses ◽

External Potassium ◽

Prolonged Response ◽

Plateau Level ◽

Potassium Addition

Replacement of Ringer's chloride by a variety of nonpenetrating anions results in prolonged electrical and mechanical responses of muscle to stimulation. The ‘negative after-potential’ is characterized by a slowly increasing secondary depolarization which reaches a stable plateau lasting as long as 2 minutes. After-discharge frequently occurs during early depolarization. In most fibers repolarization is relatively abrupt, but in some, slow oscillations resembling relaxation oscillations arise following the plateau, grow gradually in amplitude and, only when they are of sufficient amplitude, does the membrane repolarize. Prolonged depolarization can still be produced when the spike has failed. At times, fibers may respond with short-duration action potentials, but may be primed to give prolonged responses by previous stimuli or by increase of external potassium. Addition of chloride has no effect below a critical concentration. Reduction of sodium to 25% of normal does not change plateau level or duration. Duration of the plateau phase is decreased by potassium.

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