Treatment for Circadian Rhythm Sleep Disorders

Bright light therapy

a method used to adjust a person's circadian rhythm through intense but safe exposure to a high-intensity light source 12hrs prior to desired sleep time

process of bright light therapy

1. Individual is exposed to a bright light source

2. SCN receives this as an external cue, a zetigeber, which acts as a biological mechanism to regulate the sleep-wake cycle e.g by promoting wakefulness through the release of cortisol

3. Readjusts the circadian rhythm and ensures that sleeping and waking occur at the desired time

factors essential to successful bright light therapy

• appropriate timing of exposure sessions

• right amount of light

• safe exposure

using bright light therapy as a treatment for DSPS

1. individual is exposed to the bright light source in the morning at an appropriate waking time

2. acts as an external cue to suprachiasmatic nucleus

3. promotes wakefulness by sending signals to adrenal cortex to release cortisol

4. also helps SCN send signals for melatonin release at an earlier, more appropriate time, promoting sleep

using bright light therapy as a treatment for ASPD

1. individual is exposed to the bright light source in the evening when feeling sleepy

2. Acts as an external cue to the suprachiasmatic nucleus and promote wakefulness

3. helps SCN send signals to pineal gland for melatonin release at a later, more appropriate sleeping time

4. also encourages SCN to signal cortisol release later in the morning at a more appropriate time

using bright light therapy as a treatment for shift work related sleep disorders

1. use of bright light therapy for shift work related disorders depends on details and timing of an individuals work

2. worker is best to be exposed to the bright light source before beginning their shift, promoting wakefulness when they need to work

3. this will help promote sleepiness at a later, more suitable time (when not required to work, whether its morning or night)