Sara - Revision history

imported>Psych204B: /* Conclusions */

2012-03-18T12:00:56Z

Conclusions

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	= ~~Conclusions~~ =		= Discussion =

	(TBC)		(TBC)

imported>Psych204B: /* Background */

2012-03-18T12:00:15Z

Background

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	We want to examine the neural bases of emotional regulation in response to negative emotions associated with autobiographical memories in both an MDD and control population, and to compare the use of different strategies in those with MDD relative to non-MDD participants.		We want to examine the neural bases of emotional regulation in response to negative emotions associated with autobiographical memories in both an MDD and control population, and to compare the use of different strategies in those with MDD relative to non-MDD participants.

	Three strategies are are used here to either facilitate or undermine rumination as a response to negative emotional memories. The "feel" ~~task~~ asks individuals to focus on the feelings that arise as they recall their experiences.		Three strategies are are used here to either facilitate or undermine rumination as a response to negative emotional memories. The "feel" strategy asks individuals to focus on the feelings that arise as they recall their experiences; prior research indicates that focusing concretely on feelings tends to increase negative affect and rumination. While the "feel" strategy is intended to increase rumination, the analyze and accept strategies are intended to counteract rumination and promote adaptive self-reflection. The "analyze" strategy asks individuals to objectively analyze the reasons behind their feelings. The "accept" strategy prompts participants to recognize their feelings as transitory mental events that are distinct from the self and exist in a space of constant flux that can be mindfully observed without overwhelm.



	= Methods =		= Methods =

imported>Psych204B at 11:31, 18 March 2012

2012-03-18T11:31:12Z

← Older revision		Revision as of 11:31, 18 March 2012
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	= Background =		= Background =

	Major Depressive Disorder (MDD) is associated with self-focused rumination; people with tendencies to ruminate will focus repetitively on negative emotions and feelings of distress. These negative emotions often co-arise with memories of past experiences. Emotion regulation strategies are often a component of cognitive therapies for depression, such as reappraisal in CBT.		Major Depressive Disorder (MDD) is associated with self-focused rumination; people with tendencies to ruminate will focus repetitively on negative emotions and feelings of distress. These negative emotions often co-arise with memories of past experiences; however, many studies of the neural bases of emotional regulation have focused on responses to more immediate aversive stimuli, such as cutaneous shock. Emotion regulation strategies are often a component of cognitive therapies for depression, such as reappraisal in CBT - and yet, interestingly, neuroimaging studies of emotion regulation strategies have not found the measured changes in brain activity to align well with the brain regions considered relevant to depression.

			We want to examine the neural bases of emotional regulation in response to negative emotions associated with autobiographical memories in both an MDD and control population, and to compare the use of different strategies in those with MDD relative to non-MDD participants.

			Three strategies are are used here to either facilitate or undermine rumination as a response to negative emotional memories. The "feel" task asks individuals to focus on the feelings that arise as they recall their experiences.



	= Methods =		= Methods =
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	Participants were trained to associate memory cue words with recall of specific negative autobiographical memories, which they had described in an initial screening session. A computer protocol was used in pre-scan training to ensure participants could quickly recall the associated memory when a cue word appears, i.e. within 10 seconds. Nine memories were used per subject, and memories were matched for ratings of valence and arousal.		Participants were trained to associate memory cue words with recall of specific negative autobiographical memories, which they had described in an initial screening session. A computer protocol was used in pre-scan training to ensure participants could quickly recall the associated memory when a cue word appears, i.e. within 10 seconds. Nine memories were used per subject, and memories were matched for ratings of valence and arousal.

	Three repetitions of each of the three stimulus blocks (feel, accept, analyze) were presented to subjects in counterbalanced order. Each trial started with a 10-second memory cue phase, prompting the participant to bring to mind the cued autobiographical memory. Next, an instruction cue appeared on the screen, directing the participant to engage in either the feel, analyze, or accept strategy for 30 seconds. Subsequently, participants were prompted to rate how aroused they felt (Rating 1) and how negative they felt (Rating 2) on a 5-point scale. They were given 5 seconds for each question. After this, participants were given a spatial perception task for 30 seconds, in which they saw an arrow pointing right or left and indicated which direction it was pointing. The arrows task was chosen as an active baseline task that would not engage the emotional, regulatory, or memory processes of interest; this task has been used in prior research, and ~~the~~ prior work suggests it does not engage these processes.		Three repetitions of each of the three stimulus blocks (feel, accept, analyze) were presented to subjects in counterbalanced order. Each trial started with a 10-second memory cue phase, prompting the participant to bring to mind the cued autobiographical memory. Next, an instruction cue appeared on the screen, directing the participant to engage in either the feel, analyze, or accept strategy for 30 seconds. Subsequently, participants were prompted to rate how aroused they felt (Rating 1) and how negative they felt (Rating 2) on a 5-point scale. They were given 5 seconds for each question. After this, participants were given a spatial perception task for 30 seconds, in which they saw an arrow pointing right or left and indicated which direction it was pointing. The arrows task was chosen as an active baseline task that would not engage the emotional, regulatory, or memory processes of interest; this task has been used in prior research, and prior work suggests it does not engage these processes.


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	==== Pre-processing ====		==== Pre-processing ====

	The first 4 volumes (8s) in each functional scan were removed to allow for equilibrium effects. Functional and structural scans were processed with BET (Brain Extraction Tool) to remove the skull and nonbrain tissue. Motion correction was performed using MCFLIRT (part of FSL). Any subjects with motion exceeding 1.5mm were excluded from the analyses (N=1). Functional scans were slice-time corrected. High-pass temporal filtering was used to correct for baseline drifts, and data were spatially smoothed using a 5 mm full-width-half-maximum Gaussian kernel. Functional images were registered to the subjects' structural images using a 6 DOF transformation in FLIRT (FMRIB's Linear Image Registration Tool). Structural images were registered to MNI template space using a 12 DOF transformation in FLIRT, and this transformation was then applied to the functional images		The first 4 volumes (8s) in each functional scan were removed to allow for equilibrium effects. Functional and structural scans were processed with BET (Brain Extraction Tool) to remove the skull and nonbrain tissue. Motion correction was performed using MCFLIRT (part of FSL). Any subjects with motion exceeding 1.5mm were excluded from the analyses (N=1). Functional scans were slice-time corrected. High-pass temporal filtering was used to correct for baseline drifts, and data were spatially smoothed using a 5 mm full-width-half-maximum Gaussian kernel. Functional images were registered to the subjects' structural images using a 6 DOF transformation in FLIRT (FMRIB's Linear Image Registration Tool). Structural images were registered to MNI template space using a 12 DOF transformation in FLIRT, and this transformation was then applied to the functional images.


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	== Accept Task ==		== Accept Task ==
			<br>

			[[File:Mdd_mean_accept_mean.png \|thumb\|500px\|center\| Mean Activation on the Accept Task, MDD group]]
			<br>
			[[File:Ctl_mean_accept_mean.png \|thumb\|500px\|center\| Mean Activation on the Accept Task, CTL group]]

	<br>		<br>
	[[File:Cope2_mdd_v_ctl_zstat4.png \|thumb\|500px\|center\| Accept ~~Mean~~, MDD > CTL]]		[[File:Cope2_mdd_v_ctl_zstat4.png \|thumb\|500px\|center\| Mean Activation on the Accept Task, MDD > CTL]]
	<br>		<br>
	<br>		<br>
	[[File:Cope2_ctl_vs_mdd_zstat3.png \|thumb\|500px\|center\| Accept ~~Mean~~, CTL > MDD]]		[[File:Cope2_ctl_vs_mdd_zstat3.png \|thumb\|500px\|center\| Mean Activation on the Accept Task, CTL > MDD : No regions show higher activation in the control group versus the MDD group ]]
	<br>		<br>
	<br>		<br>
	'''MDD > CTL for Accept Task'''		'''MDD > CTL for Accept Task: Regions of Increased Activation in the MDD Group'''

	[[File:Ifg_for_accept_mean.png \|thumb\|350px\|center\| Accept Mean, MDD > CTL, Inferior Frontal Gyrus]]		[[File:Ifg_for_accept_mean.png \|thumb\|350px\|center\| Accept Mean, MDD > CTL, Inferior Frontal Gyrus]]
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	<br>		<br>

			On the accept task (relative to baseline), significantly higher activation is observed in the MDD group relative to the control group in the inferior frontal gyrus, subgenual prefrontal cortex, thalamus, precuneus, and amygdala.

			Results are reported thus far only for the mean activation on the accept task for each group and the differences in mean activation on this task between the MDD and CTL groups. More analyses need to be done on the contrasts between strategies in order to determine which areas appear to be selectively activated by the implemented strategy. Also, statistical analyses should be done relating the implemented strategies, levels of activation, and self-ratings of emotional valence and arousal after the instruction block.


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	= Conclusions =		= Conclusions =

	~~Here is where you say what your results mean.~~		(TBC)

	= References - Resources and related work =		= References - Resources and related work =

imported>Psych204B: /* Methods */

2012-03-18T03:36:47Z

Methods

← Older revision		Revision as of 03:36, 18 March 2012
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	==== ~~PRF model fits~~ ====		==== Statistical Analysis ====
	~~PRF models were fit with a 2-gaussian model.~~

	~~==== MNI space ====~~		Statistical analysis of fMRI timecourses was carried out using FEAT (fMRI Expert Analysis Tool) through modeling the following experimental task conditions at the first level: memory cue, instruction cue, rating 1, and rating 2. The arrows epoch was left as the implicit baseline. Analysis used the general linear model (GLM) and a design matrix was generated with a synthetic hemodynamic response function and its first derivative. Motion was included as a variable of no interest, to additionally control for motion. For the voxel-wise analysis of activation within groups, reported regions were thresholded at Z > 2 and a cluster probability of p < 0.05, corrected for whole-brain multiple comparisons using Gaussian random field theory (Worsley, Marrett, Neelin, & Evans, 1992).
	~~After a pRF model~~ was ~~solved for each subject~~, ~~the model was trasnformed into MNI template space~~. ~~This~~ was ~~done by first aligning~~ the ~~high resolution t1-weighted anatomical scan from each subject to an MNI template~~. ~~Since~~ the ~~pRF~~ model was ~~coregistered~~ to the t1-~~anatomical scan~~, ~~the same alignment matrix could then be applied to the pRF model~~. ~~<br>~~
	~~Once each pRF model was aligned to MNI space~~, ~~4 model parameters~~ - x, y, ~~sigma~~, ~~and r^2 - were averaged across each of the 6 subjects in each voxel~~.

	~~Et cetera~~.
			To analyze the differences in activation between control and depressed participants, participant-specific maps were carried to higher-level inter-group analyses using FMRIB’s Local Analysis of Mixed Effects (FLAME; Woolrich, Behrens, & Smith, 2004). The resulting statistical images were thresholded at Z > 1.65, corresponding to a one tailed p of 0.05, and corrected for multiple comparisons using Gaussian random field theory.

	= Results =		= Results =

imported>Psych204B at 03:13, 18 March 2012

2012-03-18T03:13:01Z

← Older revision		Revision as of 03:13, 18 March 2012
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	'''MDD > CTL for Accept Task'''		'''MDD > CTL for Accept Task'''

	[[File:Ifg_for_accept_mean.png \|thumb\|350px\|~~left~~\| Accept Mean, MDD > CTL, Inferior Frontal Gyrus]]		[[File:Ifg_for_accept_mean.png \|thumb\|350px\|center\| Accept Mean, MDD > CTL, Inferior Frontal Gyrus]]

	[[File:Subgenual_pfc_for_accept.png \|thumb\|350px\|~~right~~\| Accept Mean, MDD > CTL, Subgenual Prefrontal Cortex]]		[[File:Subgenual_pfc_for_accept.png \|thumb\|350px\|center\| Accept Mean, MDD > CTL, Subgenual Prefrontal Cortex]]

	<br>		<br>

	[[File:Thalamus_for_accept.png \|thumb\|350px\|~~left~~\| Accept Mean, MDD > CTL, Thalamus]]		[[File:Thalamus_for_accept.png \|thumb\|350px\|center\| Accept Mean, MDD > CTL, Thalamus]]

	[[File:Precuneus_accept.png \|thumb\|350px\|~~right~~\| Accept Mean, MDD > CTL, Precuneus]]		[[File:Precuneus_accept.png \|thumb\|350px\|center\| Accept Mean, MDD > CTL, Precuneus]]

	<br>		<br>

	[[File:Amygdala_for_accept.png \|thumb\|350px\|~~left~~\| Accept Mean, MDD > CTL, Amygdala]]		[[File:Amygdala_for_accept.png \|thumb\|350px\|center\| Accept Mean, MDD > CTL, Amygdala]]

			<br>






	<br>		<br>

	~~== Retinotopic models in individual subjects transformed into MNI space ==~~
	~~Some text. Some analysis. Some figures.~~

	~~== Retinotopic models in group-averaged data on the MNI template brain ==~~
	~~Some text. Some analysis. Some figures. Maybe some equations.~~




	~~== Retinotopic models in group-averaged data projected back into native space ==~~
	~~Some text. Some analysis. Some figures.~~

	= Conclusions =		= Conclusions =

imported>Psych204B: /* Accept Task */

2012-03-18T02:28:01Z

Accept Task

← Older revision		Revision as of 02:28, 18 March 2012
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	[[File:Subgenual_pfc_for_accept.png \|thumb\|350px\|right\| Accept Mean, MDD > CTL, Subgenual Prefrontal Cortex]]		[[File:Subgenual_pfc_for_accept.png \|thumb\|350px\|right\| Accept Mean, MDD > CTL, Subgenual Prefrontal Cortex]]

			<br>

			[[File:Thalamus_for_accept.png \|thumb\|350px\|left\| Accept Mean, MDD > CTL, Thalamus]]

			[[File:Precuneus_accept.png \|thumb\|350px\|right\| Accept Mean, MDD > CTL, Precuneus]]

			<br>

			[[File:Amygdala_for_accept.png \|thumb\|350px\|left\| Accept Mean, MDD > CTL, Amygdala]]

	<br>		<br>

imported>Psych204B: /* Accept Task */

2012-03-18T01:57:46Z

Accept Task

← Older revision		Revision as of 01:57, 18 March 2012
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	[[File:Cope2_mdd_v_ctl_zstat4.png \|thumb\|500px\|center\| Accept Mean, MDD > CTL]]		[[File:Cope2_mdd_v_ctl_zstat4.png \|thumb\|500px\|center\| Accept Mean, MDD > CTL]]
	<br>		<br>


	<br>		<br>
	[[File:Cope2_ctl_vs_mdd_zstat3.png \|thumb\|500px\|center\| Accept Mean, CTL > MDD]]		[[File:Cope2_ctl_vs_mdd_zstat3.png \|thumb\|500px\|center\| Accept Mean, CTL > MDD]]
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	'''MDD > CTL for Accept Task'''		'''MDD > CTL for Accept Task'''

	[[File:Ifg_for_accept_mean.png \|thumb\|~~500px~~\|~~center~~\| Accept Mean, MDD > CTL, Inferior Frontal Gyrus]]		[[File:Ifg_for_accept_mean.png \|thumb\|350px\|left\| Accept Mean, MDD > CTL, Inferior Frontal Gyrus]]

			[[File:Subgenual_pfc_for_accept.png \|thumb\|350px\|right\| Accept Mean, MDD > CTL, Subgenual Prefrontal Cortex]]

	<br>		<br>

imported>Psych204B: /* Accept Task */

2012-03-18T01:40:28Z

Accept Task

← Older revision		Revision as of 01:40, 18 March 2012
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	== Accept Task ==		== Accept Task ==

	~~Accept Mean, MDD > CTL~~
	<br>		<br>
	[[File:Cope2_mdd_v_ctl_zstat4.png \|~~600px~~\|center\| Accept Mean MDD > CTL]]		[[File:Cope2_mdd_v_ctl_zstat4.png \|thumb\|500px\|center\| Accept Mean, MDD > CTL]]
	<br>		<br>

	~~Accept Mean, CTL > MDD~~
	<br>		<br>
	[[File:Cope2_ctl_vs_mdd_zstat3.png \|~~600px~~\|center\| Accept Mean CTL > MDD]]		[[File:Cope2_ctl_vs_mdd_zstat3.png \|thumb\|500px\|center\| Accept Mean, CTL > MDD]]
	<br>		<br>
	<br>		<br>
	'''MDD > CTL for Accept Task'''		'''MDD > CTL for Accept Task'''
	~~Inferior Frontal Gyrus~~
	[[File:Ifg_for_accept_mean.png \|~~600px~~\|center\| Accept Mean, ~~IFG~~]]		[[File:Ifg_for_accept_mean.png \|thumb\|500px\|center\| Accept Mean, MDD > CTL, Inferior Frontal Gyrus]]

			<br>

	== Retinotopic models in individual subjects transformed into MNI space ==		== Retinotopic models in individual subjects transformed into MNI space ==

imported>Psych204B: /* Accept Task */

2012-03-18T01:27:50Z

Accept Task

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 == Accept Task ==
-Some text. Some analysis. Some figures.
 == Retinotopic models in individual subjects transformed into MNI space ==

imported>Psych204B at 15:00, 17 March 2012

2012-03-17T15:00:22Z

@@ Line 42: / Line 42: @@
 ==== Pre-processing ====
-All data were slice-time corrected, motion corrected, and repeated scans were averaged together to create a single average scan for each subject. Et cetera.
 ==== PRF model fits ====
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 == Retinotopic models in group-averaged data projected back into native space ==