Fear extinction learning improvement in PTSD after EMDR therapy: an fMRI study

Figures & data

Table 1. Socio-demographic characteristic for the sample.

	EMDR Group	Wait-list Group	Significativity
Socio-demographic characteristic
Sex ratio (m/w)	6/6	5/7	NS
Age, years	45.25 (7.83)	40.08 (10.54)	NS
Education level, years	8.08 (2.71)	8.08 (2.9)	NS
Duration of illness, days	365	426	NS
Duration of therapy, hours	2.83 (0.38)	2.75 (0.45)	NS
Delay between T0 and T1	96.75 (95.23)	149.25 (122.42)	NS
Psychometric scales
PCLS at T0	59.5 (12.93)	60.75 (13.05)	NS
IES at T0	48.25 (17.31)	58.41 (11.18)	NS
BECK at T0	13.5 (5.02)	12.17 (7.33)	NS
PCLS at T1	28.41 (7.73)	53.58 (18.77)	p < .001
IES at T1	9 (7.9)	43.5 (24.39)	p < .001
BECK at T1	5.75 (4.49)	11.58 (8.37)	p < .05
Type of trauma
Accident	4	3	NS
Holdup	1	2	NS
Physical assault	7	7	NS
Use of psychiatric medications	6/12	9/12	NS
Selective serotonin reuptake inhibitors	4	6
Hypnotic	2	3
Psychiatric comorbidities in the MINI at T0
Major depressive episode	8/12	8/12	NS
Suicidality	5/12	2/12	NS
Manic or hypomanic episode	0/12	0/12	NS
Anxiety disorder	10/12	9/12	NS
Substance abuse or dependence	2/12	0/12	NS

Values in bold represent significant results.

Figure 1. Changes in behavioural responses during extinction before and after recovery.

There was a significant group × time interaction for the behavioural responses during fear extinction (F = 5.27 and p < .05). In the EMDR group after treatment, fear responses in the late extinction (E6) were significantly lower than the early extinction (p < .01). Fear responses in E6 after treatment were significantly lower than before treatment (p < .05). Fear expectation in E6 at T1 was lower in the EMDR than in the WL group (p < .05).

Table 2. Fear expectations during the fear condition and extinction protocol for the two groups before (T0) and after (T1) EMDR therapy.

		EMDR group	Wait-list group
C1	T0	0.125 (0.22)	0.35 (0.18)
	T1	0.5 (0.12)	0.46 (0.14)
C2	T0	0.55 (0.15)	0.42 (0.14)
	T1	0.65 (0.11)	0.57 (0.22)
C3	T0	0.475 (0.15)	0.42 (0.23)
	T1	0.62 (0.1)	0.6 (0.13)
C4	T0	0.45 (0.11)	0.6 (0.17)
	T1	0.67 (0.09)	0.57 (0.16)
C5	T0	0.4 (0.15)	0.53 (0.14)
	T1	0.62 (0.13)	0.25 (0.21)
C6	T0	0.42 (0.14)	0.35 (0.22)
	T1	0.75 (0.09)	0.39 (0.21)
E1	T0	0.55 (0.16)	0.64 (0.13)
	T1	0.45 (0.15)	0.42 (0.2)
E2	T0	0.6 (0.13)	0.71 (0.15)
	T1	0.25 (0.14)	0.26 (0.19)
E3	T0	0.47 (0.14)	0.67 (0.10)
	T1	0.15 (0.13)	0.17 (0.16)
E4	T0	0.2 (0.11)	0.42 (0.13)
	T1	0.02 (0.12)	0.15 (0.18)
E5	T0	0.32 (0.12)	0.25 (0.17)
	T1	0.08 (0.09)	0.21 (0.19)
E6	T0	0.25 (0.11)	0.28 (0.16)
	T1	0.07 (0.05)	0.53 (0.16)

Behavioural responses for the difference between CS+ minus CS- were averaged on four consecutive presentations for the conditioning and the extinction, resulting in six values per conditioning and extinction phases. Values represent average and standard error on fear expectation per group.

Figure 2. Brain representation of the significant clusters for the EMDR group (T1 (E1(CS+ vs CS-)-E6(CS+ vs CS-)))-T0(E1(CS+ vs CS-)-E6) minus wait-list group (T1 (E1(CS+ vs CS-)-E6(CS+ vs CS-)))-T0(E1(CS+ vs CS-)-E6) contrast. (a): right amygdala; left amygdala and hippocampus. (b): right BA8. (c): right BA47 and insula. (d): left Heschl gyrus. (e): left BA31. The factorial design analysis has evidenced six significant clusters when considering the EMDR group vs the Wait-List group for the contrast after minus before therapy for early E1 minus late E6 (CS+ minus CS-). Significance level was defined as cluster p-values < .05 after correction for family-wise error (FWE).

Figure 3. Functional connectivity.Positive connectivity After treatment, at the end of the extinction the left amygdala in the EMDR group shows an increase of its connectivity with the left posterior division of the inferior temporal gyrus, a part of the temporal pole (F = 0.87; intensity = 4.41; p FDR < .022) compared to the wait-list group. Lateral and anterior view. Negative connectivity After treatment, at the end of the extinction, the left hippocampus in the EMDR group shows a decrease of its connectivity with the left superior parietal lobule (F = 1.13; intensity = 4.73; p FDR < .01) compared to the wait-list group. Lateral and anterior view. After treatment, at the end of the extinction, the right insula in the EMDR group shows a decrease of its connectivity with the right ventral entorhinal cortex (BA 28) (F = 1.95; intensity = 4.8; p FDR < .008) compared to the wait-list group. Anterior and lateral view. Fear extinction learning improvement in PTSD after EMDR therapy: an fMRI study.