Environmental Therapeutics . . .

. . . harnessing neglected properties of light, dark, and air to meet the challenges of mental and physical health in contemporary life.

Therapeutic applications include:

seasonal affective disorder
non-seasonal depression
bipolar disorder (mania/hypomania)
mood changes during pregnancy

shift work disruption
sleep regulation and optimization
COVID isolation fatigue/stress
circadian rhythm adjustment

Discover CET's free e-book collection

Our latest “Perinatal Depression: How Light Makes Pregnancy Brighter” is now available.

Read it now!

Journal Watch

CET researchers scan the journals as soon as new issues are published and recommend the best in environmental therapeutics for our visitors to ponder.

See the list

Our New Lives With COVID-19

CET and friends in the research community offer a unique set of suggestions for dealing with sleep,
mood changes, and the virus itself – along with some noteworthy history about pandemics and vaccines.

Meet our experts, and a patient whose life turned around with light therapy, in a 6-minute video on seasonal and nonseasonal depression.

How does light work?

Light is a powerful antidepressant and is also the most powerful known zeitgeber (time-setter) for the internal biological clocks of the body. Catch up on the latest findings here.

Variations on the SAD Experience

Symptoms of seasonal affective disorder vary widely. A group of “atypical” symptoms predicts the onset of winter depression and the response to light therapy.

Light Therapy: Its Discovery and Applications

Light therapy is one of the most exciting, unexpected, and scientifically interesting developments in medicine today. It stands apart as one of the rare treatments that developed directly out of basic research in neurobiology: an impressive story of intellectual preparedness and bench-to-bedside crosstalk.

Melatonin and Its Uses

This popular supplement — actually an active hormone — has been widely marketed in the U.S. with doses and claims that don’t pass muster. Did you know that melatonin does not put you to sleep at bedtime, but can konk you out in the middle of the day? Find out the facts here, from the field’s leading research scientist.

How to Select a Light Box

You want a device that actually works to banish blue mood, increase alertness and energy, and correct off-schedule sleep times. Despite advertising claims, you won’t find this from the most aggressively marketed devices. Here we explain the benchmark light box properties that have been proved effective in clinical trials.

Why Should Someone Learn About Depression?

Talking about depression with someone who is depressed — or seems depressed — isn’t easy. The discussion can be wrenching, surprising, and the biggest favor friends can offer each other. Each case is unique, and the pathways to solutions are ever-expanding as the science inches forward.

Teen sleep: Too late, too little, or both?

The trials and tribulations of adolescence are manifold — the products of both biology and social convention. Sleep is a case in point: your circadian rhythm slows down so you’re not ready for sleep at the “right” time, while your school day forces early awakening, leaving you anxious and depleted. How can we solve the conflict?

Power Naps Bring Power

Feeling the need to nap is not a sign of slothfulness. Indeed, it can be empowering, if you follow a few basic rules. Find out when is best and when it degrades nighttime sleep. Find out the length of a productive nap versus one that lays you flat out, wishing you hadn’t done it.

The Secrets of Falling Asleep

My secret may not work for you, and yours may not work for me, because we are built to sleep differently. Midnight for you might feel like early evening for me. Find your best-fit solution: measure your internal clock against the clock on the wall, learn when to seek light and when to control it — and even how to set your hand and foot temperature to bring on those Zzzzs.

Sleep and Aging: Why Does Sleep Change as We Age?

Do you think older folks need less sleep than when they were young, just because they wake up earlier? Actually, less sleep presents a risk for quality of life as well as serious geriatric illness. Learn how to adjust meds, naps, and light to normalize sleep timing and duration, in the context of treating illnesses that may occur in old age.

The Night, and Sleep, Need Darkness

Can you see streetlights through the window in your bedroom? Or do you let the TV turn itself off after you’ve fallen asleep? Controlling these factors can be key to controlling insomnia without recourse to prescription drugs. Let your brain produce its own melatonin in darkness! And learn about non-interfering, blue-free bedroom lighting.

Depression and Anxiety in COVID-19 Survivors

The Night and Sleep Need Darkness

Sleep and Aging: Why Does Sleep Change as We Age

Secrets of Falling Asleep

Five Tips to Give Your Baby the Best Sleep in the World

Select a category that interests you.

We have a vast library of answered questions.

Faculty at Columbia, Yale, the University Hospitals of Basel and Copenhagen, the Russian Academy of Medical Sciences, and other top institutions around the world serve as our experts. Their cutting edge research offers snapshots of our interdisciplinary enterprise. Please note that the recommendations of our experts are not a substitute for the advice of your own physician or therapist.

Join Us

We welcome your participation as well as your support.

Fund our projects and let us help more people.

We need your donations to keep you on top
of the latest therapeutic and scientific advances.

Maintaining and expanding our website requires our visitors’ and colleagues’ support.

Come visit us!

31 Harvard St, Worcester, MA, 01609

Book your visit

Brain and Body

Body Clock

Light and Air

Environmental Therapeutics . . .

For everyone

For professionals

Self-assessments with feedback

Discover CET's free e-book collection

Light and Body Clock Therapy for Beginners

Our New Lives With COVID-19

Meet our experts, and a patient whose life turned around with light therapy, in a 6-minute video on seasonal and nonseasonal depression.

How does light work?

Variations on the SAD Experience

Light Therapy: Its Discovery and Applications

Melatonin and Its Uses

How to Select a Light Box

Why Should Someone Learn About Depression?

Teen sleep: Too late, too little, or both?

Power Naps Bring Power

The Secrets of Falling Asleep

Sleep and Aging: Why Does Sleep Change as We Age?

The Night, and Sleep, Need Darkness

Depression and Anxiety in COVID-19 Survivors

The Night and Sleep Need Darkness

Sleep and Aging: Why Does Sleep Change as We Age

Secrets of Falling Asleep

Five Tips to Give Your Baby the Best Sleep in the World

Ask Our Experts

Select a category that interests you.

Categories

Join Us

We need your donations to keep you on top
of the latest therapeutic and scientific advances.

Come visit us!

Brain and Body

Body Clock

Light and Air

Environmental Therapeutics . . .

For everyone

For professionals

Self-assessments with feedback

Discover CET's free e-book collection

Light and Body Clock Therapy for Beginners

Our New Lives With COVID-19

Meet our experts, and a patient whose life turned around with light therapy, in a 6-minute video on seasonal and nonseasonal depression.

How does light work?

Variations on the SAD Experience

Light Therapy: Its Discovery and Applications

Melatonin and Its Uses

How to Select a Light Box

Why Should Someone Learn About Depression?

Teen sleep: Too late, too little, or both?

Power Naps Bring Power

The Secrets of Falling Asleep

Sleep and Aging: Why Does Sleep Change as We Age?

The Night, and Sleep, Need Darkness

Depression and Anxiety in COVID-19 Survivors

The Night and Sleep Need Darkness

Sleep and Aging: Why Does Sleep Change as We Age

Secrets of Falling Asleep

Five Tips to Give Your Baby the Best Sleep in the World

Ask Our Experts

Select a category that interests you.

Categories

Join Us

We need your donations to keep you on top of the latest therapeutic and scientific advances.

Come visit us!

We need your donations to keep you on top
of the latest therapeutic and scientific advances.