Sleep Self-Regulation Using Mental Imagery

Using Mental Imagery to Deliver Self-Regulation Techniques That Target Sleep Initiation Behaviors and Pre-Sleep Arousal

This randomised controlled trial assessed the efficacy of four mental imagery techniques for improving sleep and its related behaviour: (1) imagery focused on reducing arousal levels; (2) imagery incorporating implementation intentions (a strategy designed to link specified behaviour with the anticipated context) for sleep-related behaviour; (3) a combination of imagery using arousal reduction and implementation intention strategies; or (4) a condition where participants were asked to imagine their typical post work activities.

Study Overview

• Status: Completed
• Conditions: Insomnia; Sleep Deprivation
• Intervention / Treatment: Behavioral: Sleep Self-Regulation Using Mental Imagery

Detailed Description

Sleep deprivation is a significant health issue in the modern workplace. We conducted a randomized controlled trial to test the efficacy of techniques involving mental imagery promoting relaxation (arousal reduction; AR) and simulation of the appropriate sleep behavior in the likely environments (implementation intentions; II) in a population of daytime employees

• Study Type: Interventional
• Enrollment (Actual): 104
• Phase: Not Applicable

Contacts and Locations

Study Locations

• New Zealand
  • Auckland, New Zealand
    • 10 Private Businesses in the Region

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (ADULT, OLDER_ADULT)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• ability to read and write in English;
• full-time employment;
• work shifts during daytime hours (i.e., participants were excluded if they worked night shifts either through the organization or through a secondary job) in a position that provided daily access to email;
• a score of five or greater on the Pittsburgh Sleep Quality Inventory (PSQI) which indicates at least moderate difficulties in two or more areas (e.g., sleep quality and daytime dysfunction);

Exclusion Criteria:

• An identifiable biological cause of current sleep deprivation (e.g., sleep apnoea, narcolepsy, restless leg syndrome, periodic limb movement disorder, or pregnancy)
• An identified psychological disorder
• Caring for a child under the age of 5 or have a reason outside of work that caused them to regularly lack sleep.
• Incomplete data (over 50% of daily data missing or missing final follow-up assessment

Study Plan

How is the study designed?

Design Details

• Primary Purpose: TREATMENT
• Allocation: RANDOMIZED
• Interventional Model: FACTORIAL
• Masking: DOUBLE

Number of Arms

4

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
ACTIVE_COMPARATOR: Arousal reduction using guided imagery; Sleep Self-Regulation Using Mental Imagery: Participants in the arousal reduction condition were instructed to imagine wearing a backpack loaded with their worries, then putting the heavy backpack down, and then experiencing the relief and freedom from tension.	Behavioral: Sleep Self-Regulation Using Mental Imagery; Comparison of two forms of mental imagery to instigate behaviors that assist in the sleeping process; Other Names: behavior change; mental imagery; guided imagery; Implementation intentions; sleep; self-regulation
ACTIVE_COMPARATOR: Mental simulation of sleep behavior; Sleep Self-Regulation Using Mental Imagery: Participants in this condition received instructions to visualize a specific behavioral plan designed to meet the goal of obtaining quality sleep each night through the practice of certain behaviors. To form the behavioral plan, participants visualised changing into comfortable clothes and taking time to relax prior to going to bed, the time they planned to go to sleep, where they planned to sleep, and the bedtime routine they follow to help them to get to sleep. At bedtime, they were instructed to mentally run through a checklist of these behaviors and then do any behaviors that they had not yet completed.	Behavioral: Sleep Self-Regulation Using Mental Imagery; Comparison of two forms of mental imagery to instigate behaviors that assist in the sleeping process; Other Names: behavior change; mental imagery; guided imagery; Implementation intentions; sleep; self-regulation
ACTIVE_COMPARATOR: Combination; Sleep Self-Regulation Using Mental Imagery: Participants in this condition were asked to practice a combination of the guided imagery (for relaxation) and mental simulation imagery for sleep-related behaviour	Behavioral: Sleep Self-Regulation Using Mental Imagery; Comparison of two forms of mental imagery to instigate behaviors that assist in the sleeping process; Other Names: behavior change; mental imagery; guided imagery; Implementation intentions; sleep; self-regulation
SHAM_COMPARATOR: Control; Sleep Self-Regulation Using Mental Imagery: Participants in this condition were asked to imagine a typical post work activity	Behavioral: Sleep Self-Regulation Using Mental Imagery; Comparison of two forms of mental imagery to instigate behaviors that assist in the sleeping process; Other Names: behavior change; mental imagery; guided imagery; Implementation intentions; sleep; self-regulation

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Sleep Quality	Assessed using the Pittsburgh Sleep Quality Index (PSQI; Buysse et al, 1989).The PSQI includes 19 items that assess sleep quality, hours of sleep, sleep onset length, sleep efficiency, sleep disturbances, use of medication and daytime. Item ratings are recoded and combined to form seven component scores. These scores are then summed into a global score ranging from 0(no difficulty) to 21(severe difficulties in all areas). Daily sleep quality was assessed with five PSQI items.	Baseline and at 3 weeks. Data will also be presented for every day for the duration of the 3 week period so change can be reported.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Negative Sleep Habits	The Sleep Hygiene Index (Mastin et al, 2006). Respondents rate on a scale from 1 (never) to 5 (all the time) how frequently they engaged in 13 behaviors (e.g. "I take naps lasting two or more hours"). Ratings were summed to provide a total negative sleep habit frequency score.	Baseline and Final follow-up (at 21-days)
Sleep Efficacy	Participants rated their sleep self-efficacy with the item, "how confident are you that you can take the actions necessary to get a good sleep tonight?" Sleep response efficacy was rated with the item "how confident are you that you will actually get a good sleep tonight?" ratings ranged from 1 (not at all confident) to 10 (very confident), and they were summed; r=.69, p<.01 at baseline and r=.20, p<.05 at final follow-up.	Baseline and final follow-up (at 21 days)
Pre-Sleep Arousal	The Pre-sleep Arousal Scale (Nicasso et al, 1985) includes an 8-item somatic subscale (e.g. "how often in the last week before bed have you had a tight, tense feeling in your muscles?") and an 8-item cognitive subscale (e.g. "how often in the last week before bed do you review or ponder events of the day?"). Ratings range from 1 (not at all) to 5 (extremely) and are summed to generate scores.	Baseline and final follow-up (Day 21)
Imagery Adherence	Measure adapted from the Vividness of Imagery Questionnaire (White et al, 1978). Participants rated the vividness of the following images: (1) putting things into a bag, (2) releasing a bag, (3) getting home from work, (4) relaxing at home, (5) their night-time routine, (6) the time that they visualised going to bed, (7) the environment of their bedroom, (8) the details of the bed they are sleeping in, (9) the image of themselves falling asleep. Response options were: 1 (no image at all) 2 (vague and dim), 3 (somewhat vivid), 4 (reasonably clear), and 5 (perfectly clear and vivid).	Post-session, Daily, Final follow-up (21 days)
Action Planning	An adaptation of the action planning measure developed by Luszczynska and Schwarzer (2003) was used. The items included: "I have made a detailed plan for (1) how I am going to wind down before going to sleep (2) how I am going to prepare for bed (3) how I am going to prepare the place where I will sleep, and (4) the time when I go to sleep". Responses ranged from 1 (not at all) to 7 (very much); ratings were summed to generate scores.	Baseline, Final follow-up (Day 21)

Collaborators and Investigators

• Sponsor: University of Auckland, New Zealand
• Investigators: Principal Investigator: Marisa H Loft, PhD, Monash University (Sunway Campus, Malaysia); Study Director: Linda D Cameron, PhD, University of California, Merced

Study record dates

Study Major Dates

• Study Start: October 1, 2008
• Primary Completion (ACTUAL): April 1, 2010
• Study Completion (ACTUAL): April 1, 2010

Study Registration Dates

• First Submitted: July 18, 2012
• First Submitted That Met QC Criteria: July 19, 2012
• First Posted (ESTIMATE): July 24, 2012

Study Record Updates

• Last Update Posted (ESTIMATE): July 24, 2012
• Last Update Submitted That Met QC Criteria: July 19, 2012
• Last Verified: July 1, 2012

More Information

Terms related to this study

• Keywords: Sleep; intervention; self-regulation; Implementation intentions; mental simulation
• Additional Relevant MeSH Terms: Mental Disorders; Nervous System Diseases; Dyssomnias; Sleep Wake Disorders; Neurologic Manifestations; Sleep Deprivation
• Other Study ID Numbers: IISleepTrial12