Hansen holds a master's degree in ethnomusicology[2] and has written magazine articles and liner notes on recording artists outside of the novelty genre.

He is credited with introducing new generations of listeners to artists of the early and middle 20th century whom they might not have otherwise discovered, such as Harry McClintock, Spike Jones, Jimmy Durante, Benny Bell, Rusty Warren, Yogi Yorgesson, Nervous Norvus, Allan Sherman, Ray Stevens, Candy Candido, Stan Freberg, and Tom Lehrer, as well as helping to bring "Weird Al" Yankovic to national attention.

[3] After earning his master's degree, he lived for two years "in a big house on a hill" in Topanga Canyon with members of the rock band Spirit.

He also served briefly as a roadie for Spirit, and for Canned Heat, before being hired as an A&R man, or talent scout, for Specialty Records.

The Westwood One period marked the height of the show's national popularity; it was carried in most major radio markets, airing mainly on FM rock stations, usually late on Sunday evenings.

It was under Young's guidance that the show gained in popularity, mainly due to his willingness to foster relationships with national media and with nationally known and up-and-coming artists, including John Mammoser, Judy Tenuta, Emo Philips, Pinkard and Bowden, Wally Wingert, and Mark Davis (Richard Cheese).

Between the mid-1970s and the mid-1990s, Hansen continued to do live broadcasts on KMET and other Los Angeles area stations, in addition to his weekly taped syndicated show.

The program's opening theme is an instrumental version of "Pico and Sepulveda" recorded for the show by The Roto Rooter Good Time Christmas Band (during the early years on KMET, it had been “Sugar Blues” by Clyde McCoy).

The same Los Angeles area group recorded some of the musical teasers used on the show, such as "It's time for number one...." The other "countdown" intros come from "Barstow" by the American maverick composer Harry Partch.

Hansen's opening line, "Wind up your radios," refers to the rare 78rpm novelty records from the days of wind-up phonographs that he has featured on the show, especially in its early years.

Since 1987, and continuing as of 2024, Whimsical Will (real name: William Simpson[10]) produces a weekly "Demented News" segment for the show.

Starting in the late 1980s, the show began to lose affiliates, a victim of media consolidation and other changes in the radio industry that were pushing many alternative rock stations and individualistic broadcasters off the air.

"[9] After approximately two and a half years, and no significant change in the show's financial situation, the Dr. Demento official website announced on June 6, 2010, that the show that aired that weekend would be the final broadcast in the terrestrial radio version; however, new episodes of the online streaming version would still continue to be produced for the foreseeable future, with new episodes posted every Saturday.

In addition, according to the site, "...by special agreement and due to contractual considerations, a version of the internet show will be heard weekly on KACV-FM (in Amarillo, Texas), at least through the summer.

The weekly "Funny Five" has been replaced by a monthly Top Ten in order to allow for more comprehensive special topic segments.

In April 2013, Meep Morp Studios began seeking donations to fund a documentary named Under the Smogberry Trees: The True Story of Dr. Demento through Kickstarter.

[19] Meep Morp stated that, after the film had substantially been completed and the studio prepared to begin taping the interview portions with Hansen in July 2014, he abruptly refused the interview and issued a cease and desist order to the studio instead, stating that he and Talonian would be taking full control of the film and its profits.

The show helped revive and maintain interest in novelty hits from the 1950s and 1960s that received scant airplay on mainstream pop or oldies radio stations, including "Alley Oop" by The Hollywood Argyles, "The Ballad of Irving" by Frank Gallop, "The Battle of Kookamonga" by Homer and Jethro, "Monster Mash" by Bobby "Boris" Pickett, "Hello Muddah, Hello Faddah (A Letter from Camp)" by Allan Sherman, "I Want My Baby Back" by Jimmy Cross, and "They're Coming to Take Me Away, Ha-Haaa!"

Another frequently featured artist was Frank Zappa, whom Hansen cited as a major influence on the show and who appeared several times as a guest.

Christopher Guest, Michael McKean and Harry Shearer appeared in full costume and stayed in character for a three-hour visit.

Similar "big moments" occurred in a visit from Screamin' Jay Hawkins ("I Put a Spell on You"), when the singer appeared in the studios in Culver City dressed in black cape, distributing explosive flash paper to great effect, and when Mel Brooks came in for an interview and was presented with an "absolutely HUGE" cheesecake from Canter's Deli on Fairfax Avenue.

Dr. Demento was parodied in an episode of Mr. Show with Bob and David as "Dr. Retarded: Novelty Record Collector and Chief Head of Surgery, Mass General" and is featured as an expert in songs about "paranormal monster parties".