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REM sleep, prefrontal theta, and the consolidation of human emotional memory.

Nishida M, Pearsall J, Buckner RL, Walker MP - Cereb. Cortex (2008)

Bottom Line: Sleep also facilitates offline memory processing, resulting in superior recall the next day.Subjects that napped showed a consolidation benefit for emotional but not neutral memories.The No-Nap control group showed no evidence of a consolidation benefit for either memory type.

View Article: PubMed Central - PubMed

Affiliation: Sleep and Neuroimaging Laboratory Department of Psychology and Helen Wills Neuroscience Institute, University of California, Berkeley, CA 94702-1650, USA.

ABSTRACT
Both emotion and sleep are independently known to modulate declarative memory. Memory can be facilitated by emotion, leading to enhanced consolidation across increasing time delays. Sleep also facilitates offline memory processing, resulting in superior recall the next day. Here we explore whether rapid eye movement (REM) sleep, and aspects of its unique neurophysiology, underlie these convergent influences on memory. Using a nap paradigm, we measured the consolidation of neutral and negative emotional memories, and the association with REM-sleep electrophysiology. Subjects that napped showed a consolidation benefit for emotional but not neutral memories. The No-Nap control group showed no evidence of a consolidation benefit for either memory type. Within the Nap group, the extent of emotional memory facilitation was significantly correlated with the amount of REM sleep and also with right-dominant prefrontal theta power during REM. Together, these data support the role of REM-sleep neurobiology in the consolidation of emotional human memories, findings that have direct translational implications for affective psychiatric and mood disorders.

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Related in: MedlinePlus

(A) Correlation strength (Person's r-value) between offline benefit for emotional memory in the Nap group (i.e., the d′ benefit expressed in Fig. 2B) and the relative right versus left prefrontal spectral-band power ([F4 − F3]), illustrating a significant positive correlation in the theta-band range with the extent of offline emotional memory consolidation (R = 0.61, P = 0.03), (B) a more fine-grained analysis of this same correlation for incremental power spectrum densities within each band, expressed in average 0.5-Hz bins. Correlation strength is represented by the color range, demonstrating significant correlations within the Theta frequency band, and (C) exhibiting a maximum significance at the 5.75-Hz bin, displayed on right figure panel.
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fig5: (A) Correlation strength (Person's r-value) between offline benefit for emotional memory in the Nap group (i.e., the d′ benefit expressed in Fig. 2B) and the relative right versus left prefrontal spectral-band power ([F4 − F3]), illustrating a significant positive correlation in the theta-band range with the extent of offline emotional memory consolidation (R = 0.61, P = 0.03), (B) a more fine-grained analysis of this same correlation for incremental power spectrum densities within each band, expressed in average 0.5-Hz bins. Correlation strength is represented by the color range, demonstrating significant correlations within the Theta frequency band, and (C) exhibiting a maximum significance at the 5.75-Hz bin, displayed on right figure panel.

Mentions: The extent of right-lateralized prefrontal theta activity ([F4 − F3]) demonstrated a significant and positive correlation with the offline emotional memory benefit (Fig. 5A ; R = 0.61, P < 0.03, but did not reach the conservative Bonferroni corrected threshold for multiple comparisons; P = 0.013). Indeed, this right-sided association between theta power and emotional memory improvement was also evident when examining each electrode independently (see Supplemental Figs 2 and 3). The theta correlation was not observed at central electrode sites ([C4 − C3] or either electrode by themselves; all P > 0.20). No other frequency band at frontal (or central) regions correlated with the extent of offline improvement in emotional memory (all P > 0.15), and no association between REM-sleep theta power was observed with the offline change in neutral memory at frontal or central regions (all P > 0.14).


REM sleep, prefrontal theta, and the consolidation of human emotional memory.

Nishida M, Pearsall J, Buckner RL, Walker MP - Cereb. Cortex (2008)

(A) Correlation strength (Person's r-value) between offline benefit for emotional memory in the Nap group (i.e., the d′ benefit expressed in Fig. 2B) and the relative right versus left prefrontal spectral-band power ([F4 − F3]), illustrating a significant positive correlation in the theta-band range with the extent of offline emotional memory consolidation (R = 0.61, P = 0.03), (B) a more fine-grained analysis of this same correlation for incremental power spectrum densities within each band, expressed in average 0.5-Hz bins. Correlation strength is represented by the color range, demonstrating significant correlations within the Theta frequency band, and (C) exhibiting a maximum significance at the 5.75-Hz bin, displayed on right figure panel.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2665156&req=5

fig5: (A) Correlation strength (Person's r-value) between offline benefit for emotional memory in the Nap group (i.e., the d′ benefit expressed in Fig. 2B) and the relative right versus left prefrontal spectral-band power ([F4 − F3]), illustrating a significant positive correlation in the theta-band range with the extent of offline emotional memory consolidation (R = 0.61, P = 0.03), (B) a more fine-grained analysis of this same correlation for incremental power spectrum densities within each band, expressed in average 0.5-Hz bins. Correlation strength is represented by the color range, demonstrating significant correlations within the Theta frequency band, and (C) exhibiting a maximum significance at the 5.75-Hz bin, displayed on right figure panel.
Mentions: The extent of right-lateralized prefrontal theta activity ([F4 − F3]) demonstrated a significant and positive correlation with the offline emotional memory benefit (Fig. 5A ; R = 0.61, P < 0.03, but did not reach the conservative Bonferroni corrected threshold for multiple comparisons; P = 0.013). Indeed, this right-sided association between theta power and emotional memory improvement was also evident when examining each electrode independently (see Supplemental Figs 2 and 3). The theta correlation was not observed at central electrode sites ([C4 − C3] or either electrode by themselves; all P > 0.20). No other frequency band at frontal (or central) regions correlated with the extent of offline improvement in emotional memory (all P > 0.15), and no association between REM-sleep theta power was observed with the offline change in neutral memory at frontal or central regions (all P > 0.14).

Bottom Line: Sleep also facilitates offline memory processing, resulting in superior recall the next day.Subjects that napped showed a consolidation benefit for emotional but not neutral memories.The No-Nap control group showed no evidence of a consolidation benefit for either memory type.

View Article: PubMed Central - PubMed

Affiliation: Sleep and Neuroimaging Laboratory Department of Psychology and Helen Wills Neuroscience Institute, University of California, Berkeley, CA 94702-1650, USA.

ABSTRACT
Both emotion and sleep are independently known to modulate declarative memory. Memory can be facilitated by emotion, leading to enhanced consolidation across increasing time delays. Sleep also facilitates offline memory processing, resulting in superior recall the next day. Here we explore whether rapid eye movement (REM) sleep, and aspects of its unique neurophysiology, underlie these convergent influences on memory. Using a nap paradigm, we measured the consolidation of neutral and negative emotional memories, and the association with REM-sleep electrophysiology. Subjects that napped showed a consolidation benefit for emotional but not neutral memories. The No-Nap control group showed no evidence of a consolidation benefit for either memory type. Within the Nap group, the extent of emotional memory facilitation was significantly correlated with the amount of REM sleep and also with right-dominant prefrontal theta power during REM. Together, these data support the role of REM-sleep neurobiology in the consolidation of emotional human memories, findings that have direct translational implications for affective psychiatric and mood disorders.

Show MeSH
Related in: MedlinePlus