Gloom is a low level of light which is so dim that there are physiological and psychological effects. Human vision at this level becomes monochrome and the place then seems dull and depressing.

People describe light conditions as gloomy when the rods in their eyes take over from the cones and so their vision becomes shades of grey as they lose their colour vision. Low light of this sort is associated with depression. This association was made as far back as the 2nd century by the ancient Greek physician, Aretaeus of Cappadocia, who said, "Lethargies are to be laid in the light and exposed to the rays of the sun, for the disease is gloom."

The naturally weak daylight during winter at extreme latitudes causes winter depression. Also, weaker electrical activity is found in the retinas of depressed people, which gives them poor visual contrast so that they see the world in grey, depressing hues. A solarium or other source of bright light may be used as light therapy to treat this.

Where artificial lighting is used, this has to be sufficient to not only illuminate the task area, but also provide sufficient background lighting to avoid a sensation of gloominess which has a negative effect on efficiency. If the task is challenging, such as playing cricket, then reaction times are found to increase significantly when the illumination declines to the gloom level. This is the level at which car drivers turn their lights on.

Amber Nicole Benson (born January 8, 1977) is an American actress, writer, film director, and film producer. She is best known for her role as Tara Maclay on the TV series Buffy the Vampire Slayer, but has also directed, produced and starred in her own films Chance (2002) and Lovers, Liars & Lunatics (2006). She is also co-director with Adam Busch of Drones.

Benson was born in Birmingham, Alabama to Edward Benson, a psychiatrist, and Diane Benson. She has a younger sister, Danielle, who is an artist. She had a mixed Christian and Jewish upbringing (her father was Jewish and her mother was Christian).

As a child, Benson studied music and dance, and performed in the Birmingham Children's Ballet, as well as in local theater. She attended high school (one of her classmates being Joey Fatone) in Orlando, Florida after her family moved there, in part to help Amber pursue acting opportunities, the most prominent of which was an unsold television series called Kids' News, in which Amber was to have been one of two main anchors. The Bensons then relocated to Los Angeles, and Amber began to very quickly land roles in films and on television.

Michele Catherine Boyd (born in Gainesville, Florida) is an American actress best known for her recurring work as Riley on the web-series The Guild.

Boyd was born to a Navy family and thus spent much of her life traveling. She has one younger sister, Allyson Boyd. She was involved in plays and musicals from a very early age up through high school, performing in everything from The King and I to Cats. Boyd was a competitive swimmer since the age of 6, eventually competing in the California Interscholastic Federation Swimming and Diving events. Boyd also has worked as a snowboarding instructor at Snow Summit Resort at Big Bear Mountain and holds a green belt in hapkido.

She has a Bachelor of Science degree in Neurobiology, Physiology and Behavior from the University of California, Davis. Before settling into her career as an actress, she did neuroscience research at Harvard Medical School and the National Institute of Health.

Boyd took up acting again while she was living on the East Coast after finishing college. She pursued modeling alongside an acting career, booking ads for Coca-Cola, Hewlett-Packard and many others. Several performances in short and independent films in New York City led to her moving to Los Angeles to more fully pursue a career in film and television.