. 2023 Jan 26;23:100516. doi: 10.1016/j.ynstr.2023.100516

Table 1.

Brief Summary of Methods and Findings in Studies of Sleep Spindles in PTSD vs. Controls.

Authors	Sample Characteristics	Sleep Comparisons	Spindle Detector	Slow and Fast Spindle Distinctions	NREM stage	Primary Hypotheses	Findings: PTSD vs. Control	Findings: Associations with Clinical Variables (post-hoc)
Dotan et al. (2008)	N = 30 (15 PTSD, 15 healthy control students)	1 night of PSG (no adaptation night); in sleep lab	Visually Scored	N/A	N2	N2 Spindle Density would be higher in PTSD relative to controls	No PTSD vs. Control differences in Spindle Density	SSRI use was associated with higher Spindle Density
Wang et al. (2020b)	N = 78 (31 PTSD, 47 controls) combat-exposed male veterans aged 18-50	2 consecutive nights of PSG, analyzed separately (no adaptation night); in sleep lab	Automated detection algorithm	Slow: 10–13 Hz	N2 and N3	N/A: Exploratory analysis of group differences in spindle amplitude, duration, oscillatory frequency, and density using discovery and replication datasets	Slow spindle frequency was higher in PTSD vs. controls	Slow spindle oscillatory frequency was correlated with CAPS-based intrusive symptom score. This effect survived multiple comparison control.
Wang et al. (2020b)			Automated detection algorithm	Fast: 13–16 Hz	N2 and N3		Slow spindle frequency was higher in PTSD vs. controls
Wang et al. (2020a)	N = 78 (31 PTSD, 47 controls) male combat-exposed veterans aged 18-50	2 consecutive nights of PSG, analyzed separately (no adaptation night); in sleep lab	Automated detection algorithm	Slow: 10–13 Hz	N2 and N3	N/A: Exploratory analysis of group differences in measures of coherence, based on the Phase Locking Value (PLV) and the Mean Phase Difference (MPD) using discovery and replication datasets	No PTSD vs. control differences in PLV. MPD for slow spindles was higher in PTSD vs. controls.	MPD was negatively correlated with total CAPS score in the sample as a whole, although not in PTSD subjects alone.
Wang et al. (2020a)			Automated detection algorithm	Fast: 13–16 Hz	N2 and N3
Denis et al. (2021)	N = 97 (45 with PTSD, 52 controls) males and females, mean age 24, with recent trauma exposure	1 night of PSG after an adaptation night, at home	Automated detection algorithm	Slow: Oscillations with peak frequency of 9–12.5 Hz;	N2 and N3	NREM spindle frequency would be higher in PTSD relative to controls.	Fast spindle frequency was higher in PTSD vs. controls	No associations surviving multiple comparisons.
Denis et al. (2021)		1 night of PSG after an adaptation night, at home	Automated detection algorithm	Fast: Oscillations with peak frequency between 12.5 and 16 Hz	N2 and N3		Fast spindle frequency was higher in PTSD vs. controls	No associations surviving multiple comparisons.
Van der Heijden et al. (2022)	N = 28 (14 with PTSD, 14 matched controls) police officers and war veterans, mean age 45, all trauma-exposed	1 night of PSG during one of two nights in sleep lab (no formal adaptation night)	Proposed automated detector of spindle-shaped activity	N/A: spindle-shaped activity in 11–16 Hz bandwidth was detected; Right frontal electrode only	N2	N/A: Examined differences between PTSD and controls in spindle activity across ranges of duration, frequency, amplitude. Amplitude-based measures of spindle activity were defined and calculated.	Spindle activity, based on a smaller difference between peak and trough amplitudes, was elevated in PTSD vs. controls and survived control for medication use.	A spindle activity index based on peak and waxing and waning amplitudes of spindle shaped fluctuations correlated with the clinical interview based intrusive memory score.