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Intrusive memories to traumatic footage: the neural basis of their encoding and involuntary recall.

Clark IA, Holmes EA, Woolrich MW, Mackay CE - Psychol Med (2015)

Bottom Line: Signal change associated with intrusive memory involuntary recall was modelled using finite impulse response basis functions.We found a widespread pattern of increased activation for Intrusive v. both Potential and Control scenes at encoding.The left inferior frontal gyrus and middle temporal gyrus showed increased activity in Intrusive scenes compared with Potential scenes, but not in Intrusive scenes compared with Control scenes.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychiatry,University of Oxford,Warneford Hospital,Oxford OX3 7NG,UK.

ABSTRACT

Background: A hallmark symptom after psychological trauma is the presence of intrusive memories. It is unclear why only some moments of trauma become intrusive, and how these memories involuntarily return to mind. Understanding the neural mechanisms involved in the encoding and involuntary recall of intrusive memories may elucidate these questions.

Method: Participants (n = 35) underwent functional magnetic resonance imaging (fMRI) while being exposed to traumatic film footage. After film viewing, participants indicated within the scanner, while undergoing fMRI, if they experienced an intrusive memory of the film. Further intrusive memories in daily life were recorded for 7 days. After 7 days, participants completed a recognition memory test. Intrusive memory encoding was captured by comparing activity at the time of viewing 'Intrusive scenes' (scenes recalled involuntarily), 'Control scenes' (scenes never recalled involuntarily) and 'Potential scenes' (scenes recalled involuntarily by others but not that individual). Signal change associated with intrusive memory involuntary recall was modelled using finite impulse response basis functions.

Results: We found a widespread pattern of increased activation for Intrusive v. both Potential and Control scenes at encoding. The left inferior frontal gyrus and middle temporal gyrus showed increased activity in Intrusive scenes compared with Potential scenes, but not in Intrusive scenes compared with Control scenes. This pattern of activation persisted when taking recognition memory performance into account. Intrusive memory involuntary recall was characterized by activity in frontal regions, notably the left inferior frontal gyrus.

Conclusions: The left inferior frontal gyrus may be implicated in both the encoding and involuntary recall of intrusive memories.

No MeSH data available.


Related in: MedlinePlus

Intrusive memory involuntary recall. (a) Whole-brain analysisshowing the increased blood oxygen level-dependent (BOLD) response for intrusivememory involuntary recall v. control button press group at thetwo time bins (0–3 s and 3–6 s in relation to the button press) showingsignificant differences in activation, and the one time bin (6–9 s) showingincreased BOLD response for the control button press group v.intrusive memory involuntary recall. (b) Region-of-interestprofile plots of the signal change observed across each time bin from −3 to +12 sin relation to the button press. Intrusive memory involuntary recall signal changeactivation is shown in pink, control button press signal change activation inlight blue. Values are means, with standard deviations represented by verticalbars. IFG, Inferior frontal gyrus.
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fig03: Intrusive memory involuntary recall. (a) Whole-brain analysisshowing the increased blood oxygen level-dependent (BOLD) response for intrusivememory involuntary recall v. control button press group at thetwo time bins (0–3 s and 3–6 s in relation to the button press) showingsignificant differences in activation, and the one time bin (6–9 s) showingincreased BOLD response for the control button press group v.intrusive memory involuntary recall. (b) Region-of-interestprofile plots of the signal change observed across each time bin from −3 to +12 sin relation to the button press. Intrusive memory involuntary recall signal changeactivation is shown in pink, control button press signal change activation inlight blue. Values are means, with standard deviations represented by verticalbars. IFG, Inferior frontal gyrus.

Mentions: Whole-brain analyses using the five time bins compared activation during intrusivememory involuntary recall (i.e. involuntary recall in the scanner soon after filmviewing) and the control button press (Fig.3a; peak voxel coordinates in Table 2). Increased activation for the intrusive memory involuntaryrecall group compared with the control button press group was seen in middle andsuperior frontal regions between 0 and 3 s and in the left IFG and bilateral operculumbetween 3 and 6 s. Increased activation for the reverse contrast was seen between 6 and9 s. No suprathreshold activation was found for either contrast between −3 and 0, and9–12 s. Fig. 3.


Intrusive memories to traumatic footage: the neural basis of their encoding and involuntary recall.

Clark IA, Holmes EA, Woolrich MW, Mackay CE - Psychol Med (2015)

Intrusive memory involuntary recall. (a) Whole-brain analysisshowing the increased blood oxygen level-dependent (BOLD) response for intrusivememory involuntary recall v. control button press group at thetwo time bins (0–3 s and 3–6 s in relation to the button press) showingsignificant differences in activation, and the one time bin (6–9 s) showingincreased BOLD response for the control button press group v.intrusive memory involuntary recall. (b) Region-of-interestprofile plots of the signal change observed across each time bin from −3 to +12 sin relation to the button press. Intrusive memory involuntary recall signal changeactivation is shown in pink, control button press signal change activation inlight blue. Values are means, with standard deviations represented by verticalbars. IFG, Inferior frontal gyrus.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4697303&req=5

fig03: Intrusive memory involuntary recall. (a) Whole-brain analysisshowing the increased blood oxygen level-dependent (BOLD) response for intrusivememory involuntary recall v. control button press group at thetwo time bins (0–3 s and 3–6 s in relation to the button press) showingsignificant differences in activation, and the one time bin (6–9 s) showingincreased BOLD response for the control button press group v.intrusive memory involuntary recall. (b) Region-of-interestprofile plots of the signal change observed across each time bin from −3 to +12 sin relation to the button press. Intrusive memory involuntary recall signal changeactivation is shown in pink, control button press signal change activation inlight blue. Values are means, with standard deviations represented by verticalbars. IFG, Inferior frontal gyrus.
Mentions: Whole-brain analyses using the five time bins compared activation during intrusivememory involuntary recall (i.e. involuntary recall in the scanner soon after filmviewing) and the control button press (Fig.3a; peak voxel coordinates in Table 2). Increased activation for the intrusive memory involuntaryrecall group compared with the control button press group was seen in middle andsuperior frontal regions between 0 and 3 s and in the left IFG and bilateral operculumbetween 3 and 6 s. Increased activation for the reverse contrast was seen between 6 and9 s. No suprathreshold activation was found for either contrast between −3 and 0, and9–12 s. Fig. 3.

Bottom Line: Signal change associated with intrusive memory involuntary recall was modelled using finite impulse response basis functions.We found a widespread pattern of increased activation for Intrusive v. both Potential and Control scenes at encoding.The left inferior frontal gyrus and middle temporal gyrus showed increased activity in Intrusive scenes compared with Potential scenes, but not in Intrusive scenes compared with Control scenes.

View Article: PubMed Central - PubMed

Affiliation: Department of Psychiatry,University of Oxford,Warneford Hospital,Oxford OX3 7NG,UK.

ABSTRACT

Background: A hallmark symptom after psychological trauma is the presence of intrusive memories. It is unclear why only some moments of trauma become intrusive, and how these memories involuntarily return to mind. Understanding the neural mechanisms involved in the encoding and involuntary recall of intrusive memories may elucidate these questions.

Method: Participants (n = 35) underwent functional magnetic resonance imaging (fMRI) while being exposed to traumatic film footage. After film viewing, participants indicated within the scanner, while undergoing fMRI, if they experienced an intrusive memory of the film. Further intrusive memories in daily life were recorded for 7 days. After 7 days, participants completed a recognition memory test. Intrusive memory encoding was captured by comparing activity at the time of viewing 'Intrusive scenes' (scenes recalled involuntarily), 'Control scenes' (scenes never recalled involuntarily) and 'Potential scenes' (scenes recalled involuntarily by others but not that individual). Signal change associated with intrusive memory involuntary recall was modelled using finite impulse response basis functions.

Results: We found a widespread pattern of increased activation for Intrusive v. both Potential and Control scenes at encoding. The left inferior frontal gyrus and middle temporal gyrus showed increased activity in Intrusive scenes compared with Potential scenes, but not in Intrusive scenes compared with Control scenes. This pattern of activation persisted when taking recognition memory performance into account. Intrusive memory involuntary recall was characterized by activity in frontal regions, notably the left inferior frontal gyrus.

Conclusions: The left inferior frontal gyrus may be implicated in both the encoding and involuntary recall of intrusive memories.

No MeSH data available.


Related in: MedlinePlus