Sense Freak

""Can't talk. Enjoying pleasures of flesh.""

- Caliban, Narbonic

Humans being the kinds of creatures we are, we tend to take a lot of things for granted. Eating, for example. As a basic biological process, it gets old fast. We never really give it any thought unless we happen upon a particularly good meal.

This isn't true for aliens who have, for whatever reason, assumed human form. Everything we take for granted is brand new for them. In particular, whenever a nonhuman becomes humanlike, they go absolutely nuts about taste.

This often happens to nonhumans who can transform, and who only rarely choose a humanlike form just to hang out with others. It's even more especially true for really alien Aliens with Bizarre Alien Biology, and even more so for creatures who don't even normally have a physical form. This and Sense Loss Sadness are two of the big reasons why Humanity Is Infectious.

Oddly, this sort of thing is almost guaranteed to be totally ignored if the alien in question assumes a physical form other than human. Given the Mysterious Animal Senses trope, that's actually pretty intriguing. (But then again...)

Compare Orgasmically Delicious, Hugh Mann, Showing Off the New Body, and (ahem) Shapeshifting Squick... And speaking of Squick, see Man, I Feel Like a Woman or Breaking in Old Habits for a very specific version...

Anime and Manga

 * In Sailor Moon, Green Esmarude- your typical Vain Sorceress strolls into a fancy shin-dig, causing heads to turn at her hot elegance - until she discovered the food table, there she immediately matches Usagi dessert for dessert in stuffing her face. This caused her extreme embarrassment once she snaps out of it.
 * A non-alien example: in chapter 386 of Bleach,
 * The eponymous Ponyo goes crazy for HAM!!!, it being the first human food she ever tastes (as well as imprinting on the first human she meets in a biiiiig, world-threatening way). It seems a minor recurring Ghibli theme of late - gaining human desires is what turns Noh-face from a neutral (if creepy) spirit to an apparently evil one in Spirited Away, and (although largely off-camera) even becomes an inverse Mysterious Animal Senses in Pom Poko (where Tanuki transformed into humans, ultimately as a side effect of their habitats being destroyed, like it so much they stay in their new form).
 * In Wild Wind, once Olgrius loses his immortality sex becomes a lot...sexier. And more taxing.
 * Referred to several times in Fullmetal Alchemist by Al, who lost his human body, and whose soul currently inhabits a suit of armor.

Comic Books

 * The Martian Manhunter is a ridiculously overpowered shapeshifting alien -- who can't get enough Oreos. There was an adorable reference to this in a Breather Episode of the otherwise fairly serious Justice League animated series.
 * Let me emphasize this even more: one of the most powerful superheroes of all, the guy with all of Superman's superpowers plus some, quite literally has an Oreo addiction. OK, so maybe it's not quite to the point of an addiction, but... the man likes his Oreos!
 * In an unfortunate twist, an arc in The Authority has, as the villain, a Prohibition-era mobster who was fused with an Energy Being seeking to psychically uplift humanity while getting a blowjob. The Energy Being was "blown away" by the physical pleasure, resulting in a fusion who had all the powers of the original Energy Being, but the power-hungry, hedonistic personality of the mobster, and who proceeded to create a multiverse-spanning corporation that sold off the natural resources of entire universes. Not a good thing.
 * Batman (of course) used this to his advantage one time. With the Bad Future world about to be destroyed by Darkseid, and being observed and recorded for posterity by Metron, a literal god, Bats convinced him he needed to make himself mortal to completely record the human experience before it was wiped from existence. Sucker.
 * Something of a subversion, too - Metron finds being human utterly boring.

Fan Fic

 * In the Sailor Moon Fanfic Suburban Senshi, after deconstructing The Power of Love for all it's worth, Miss Dream emerges from Hotaru's subconscious into the real world and... promptly gets distracted. Being a dream creature that has never felt anything, she starts touching everything she gets her hands on, eating all she wants and going to the spa, giving the senshi enough time to come Back From the Dead.

Film

 * In K-PAX, the main character, who claims to be a Starfish Alien who is inhabiting a human body to learn about Earth, says that the food available was worth the long trip. He says this while he eats an underripe banana -- peel and all!
 * The 50s Science Fiction film The Brain from Planet Arrous was about a sense freak alien brain called Gor who possessed a human body with wonderfully over-the-top results.
 * This is actually one of the reasons why the Angels in the beautiful film Wings of Desire even consider giving up everything to become ordinary people -- and it is a big, big reason.
 * In Bicentennial Man, once Andrew has a central nervous system installed, he practically begs Portia to poke him in the eye, just so he could feel the joy of pain.
 * In the first Pirates of the Caribbean movie, the cursed pirates of the Black Pearl go on and on about what sensory experiences they've most missed during the curse, and therefore what they plan to glut on once they have their nerve endings back. Captain Barbossa says the first thing he plans to do is... eat a lot of apples. In the scene this seems like an Unusual Euphemism for raping his female captive, but it later turns out he was dead serious and continues to eat apples at every opportunity throughout the series.
 * In the movie Cool World, Holli Would lectures Detective Harris about how humans "really" experience everything, especially sex. "When they do it, they reeaally do it!" When she finally becomes real, she practically acts like she's having orgasms from everything she touches.
 * Kim Basinger, again, in My Step Mother Is An Alien: alien takes human form, has this reaction to food and sex. Also, gets drunk on caffine.
 * (Also discussed on Editorial Synaesthesia) - Pretty much a core protagonist motivation in Avatar, though only the big, obvious, club-you-in-the-head one actually gets any expo; Jake (re)gaining the powers of lower body sensation and motor control. Addictive enough on an immediate basis to make one . That and, of course, being able to mentally interface with other natives, animals, and even via some kind of braid-wang thing that it probably doesn't do to think much about. Other minor stuff, such as suddenly having a tail (which appears to just flap around randomly), near-indesructibility from blunt trauma, and presumably altered vision, hearing, smell/taste, vocal cords, etc are barely touched on if at all.
 * The Cenobites of the Hellraiser series are what results when this trope is taken to a truly extreme level.
 * Though according to the comics, the Cenobites themselves can't truly feel anything anymore.

Literature
"Memnon: "You're all whores to your senses, you know that, don't you?""
 * Ax from Animorphs was an Andalite, an alien species which had developed Shapeshifting technology. During the times when he had to pose as a human, he immediately went nuts over the sensation of eating. (Andalites are mouthless Centaur-like creatures in their normal form, and absorb food -- typically grass -- through their hooves.) He almost immediately became addicted to "Cinnamon BUNZAH!!!" And to chili, chocolate, cigarette stubs (!)... as a Running Gag almost all of Ax's favorite foods began with the letter C. In a "What If" novel, he went crazy for Oreos, probably a Shout Out to the Martian Manhunter.
 * Also, Andalites don't have mouths and communicate with "Thought Speech" (telepathy). So when Ax becomes human... huuuuman, huu muh muh muh man, he loves loooooves to puh-puh-pluh- play with hissss words. This, unfortunately, tends to make him stand out.
 * Not just restricted to Ax, one book had a squad of Andalites show up, the younger, female member discovers the joys of "jelly beanzuh!" Hilarity Ensues, especially as the Animorphs are so used to Ax's displays they identify her as an Andalite the moment they hear just what she's doing. (She also asks everyone in the store what their favourite flavor/colour of Jelly Bean is, causing some parents to take away their children... quickly.)
 * After the war, bringing Andalites to Earth, giving them human morphs, and taking them to a food court becomes a kind of niche tourism industry.
 * Yeerks are subtler about this than Andalites, but it's part of what moves them away from Always Chaotic Evil. Outside their host bodies, they're blind, defenseless slugs, and controlling other organisms is the only way they can enjoy the senses other species take for granted.
 * In Diane Duane's Young Wizards series, it turns out that most aliens go nuts over the taste of chocolate. A single bar of highest-quality Earth chocolate can be used as a bribe of staggering size under the right circumstances.
 * The Auditors of Discworld are completely objective, analytical beings. In Thief of Time, one of them took on a human body and nearly died of overstimulation after eating dry toast. When the other Auditors start taking human bodies as well, the heroes fight them off with chocolate.
 * The first Auditor mentioned, who goes by the Punny Name of Myria LeJean
 * "Borrowing" as performed by Discworld Witches (psychically possessing another being for reasons of espionage, sabotage or recreation, typically as simple an animal as possible) can be very dangerous for this reason; let yourself be drawn in too closely to the host's mind whilst carried away with the sensations of, e.g. wheeling through the sky whilst hunting prey from three miles out, and you may find your own deeply intertwined with it and beginning to lose memory of who you are or the faculties to conceive of having once been human. Or at least, having a massive craving for sugar water and rather confused thought patterns on returning and awakening from possessing an entire hive of bees. Crosses over quite a lot with Mysterious Animal Senses as well.
 * Could well be a way of explaining the Faerie's behaviour in Lords and Ladies - a desire to feel a linear flow of time once again, instead of living in a place where causality has been shattered and existence is a nightmare without beginning or end.
 * Inverted with the hiver from A Hat Full of Sky. It's revealed the reason the hiver takes over the bodies of living creatures is that
 * Sword of the Galaxy has the pornographic version. To be fair, it's mentioned earlier that, because they're not used to having sensitive bodies, Trakkorians would overindulge in everything on Earth if they got one, unless they were the deeply pious type.
 * In the short story "The Sixty-Two Curses of Caliph Arenschadd" by Patricia C Wrede, a girl and her family who were cursed (very much with Awesome; they were vocally happier this way) to turn into wolves. They are immediately enthralled with the awesome sensations of hearing and smell.
 * However, raw rabbit doesn't sit too well in their human stomachs when they change back.
 * In The Dark Tower by Stephen King, Roland of Gilead comes from a Scavenger World and is completely overwhelmed by the taste of a simple tuna fish sandwich and some soda.
 * Which is explained in-universe as being due to his upbringing. A famously gluttonous man in his hometown had three sugars in his tea (or possibly coffee). Apparently they ate for function rather than taste.
 * Also in Dreamcatcher, after Mr. Grey takes control of Jonesy's body. Leading to said Mr. Grey learning the hard way that there's a difference between cooked and raw bacon.
 * Another nonhuman form example. At one point in Cliff Simak's City, scientists are researching the innermost layers of Jupiter, and discover a pitch-black, windblasted "surface" of sorts at pressures so high that the most rugged machines can barely stay together long enough to examine it. Humanity has by this time invented a means to upload one's mind into a variety of creatures temporarily, and there are simple slug-like animals roaming the Jovian surface. When this is done, the explorers find that Jupiter's surface through the senses of a slug-thing is practically an euphoric wonderland of hedonism, and Earth is practically depopulated in an overnight exodus to Jovian slugdom.
 * In I, Lucifer, the titular character, upon assuming mortal flesh, spends the first few hours of existence enjoying every sensation around -- really, everything. The feel of the toilet bowl, the taste of soap, the smell of dog piss. Every. Damn. Thing.
 * Angelics, according to pre-Heel Face Turn Memnon in Armageddon.


 * Michael-Lan's club in Pantheocide seems to back up this impression.
 * Anne Rice's Vampires are examples of this trope, due to being animated by a spirit that longed to experience human sensations.
 * Commercialised in the Neuromancer universe with SimStim. The enjoyment of experiencing things through another body, whether mundane or something you'd never normally have a chance of doing, has led to enough of a business to spawn its own extreme sport, porn, and soap opera stars and breakout hits. Case, oddly, only gets a bit of a jolt when Molly gives them both a nipple tweak. Must be all that enforced cold turkey  dulling the brain's sensory cortex.
 * In A Madness of Angels, the entities sharing Matthew's body are enthralled by pretty much everything, from taste to colors. It's been stated that if they weren't sharing a consciousness with Matthew's human personality, they'd probably have gone insane from sensory overload.
 * In the Nights Dawn Trilogy, the possessed tend to be extreme Sense Freaks. It turns out that spending a lot of time without any senses at all makes any kind of sensation something to be treasured.

Live Action TV
"Data: "I hate this! It is revolting!"
 * The aliens in Roswell put Tabasco sauce on everything. It may have been just for the taste, but could conceivably have helped them maintain human form (you never forget your first Epileptic Tree).
 * It was explained in one episode that the aliens started off with a very poor sense of taste, so they could only taste things that were either extremely spicy or extremely sweet, hence the tabasco. Their sense of taste eventually became stronger, but they still used tabasco out of habit.
 * There was an episode of Star Trek: The Next Generation featuring an alien dignitary who had been unfamiliar with the concept of eating for pleasure before he came to the Enterprise. You can imagine how that turned out.
 * This trope doesn't have to be about taste. In the Star Trek the Next Generation episode where Troi has an alien baby, the child deliberately burns himself... just for the experience.
 * And then there was the Voyager episode where The Doctor had to hide his program in Seven Of Nine's body, and immediately discovered the joys of cheesecake...
 * And in First Contact, one of the ways the Borg Queen seduces Data is to give him patches of human skin, and the sensory input therein.
 * And there's trouble that brews in Generations from Data, his freshly minted emotion chip, and an inability of the former to control the latter (realism in action!). Both massive highs and lows, which he seeks out regardless in his continual quest for knowledge and understanding of the human condition - . Not all sensefreaking has to be from a direct external stimulus.

Guinan: "More?"

Data: "Please.""

"Angel: "I love chocolate! Ugh, yech. But not, as it turns out, yogurt.""
 * In an episode of The Original Series the powerful Kelvans assume human form and take over the Enterprise, putting most of the crew in stasis. Kirk, Spock, Scotty, and McCoy recapture the ship by manipulating the Kelvan's senses; Scotty gets one into a Drinking Contest, McCoy pumps another full of stimulants, Spock psychologically manipulates another, and Kirk, naturally, seduces the female Kelvan.
 * Subverted (like so many things) in Deep Space Nine when Odo is forced to stay in his humanlike form as a punishment by the Founders. When Sisko goes to talk to him in the beginning of the next episode, he ruminates on the fact that the need and sensation of eating and drinking disgusts him, and that he'll just have to get used to it.
 * Double subverted when Odo admits he finds the sound of the bubbles in his drink "soothing"
 * Another subversion comes from TNG, in an episode where Q is turned into a human as punishment for... well, for being Q. He describes feeling fatigue and falling asleep as a horrific experience (much as a normal human might describe an illness-induced blackout), throws his back out, gets stabbed with a fork by Guinan, and generally has a miserable time of it. To give an example of his opinion on being human, at one point he quips "I can now stub my toe with the best of them."
 * In a more subtle version, Kryten of Red Dwarf became human for one episode and had great fun making exaggerated facial expressions.
 * Both continued and subverted at the same time when we find out just HOW sexually aroused a 3-million-year-old, essentially genderless being can become when transferred into the body of an average human male ... and what visual literature it is that causes said arousal. Oops.
 * Red Dwarf had another example, where (soft-light hologram) Rimmer swaps minds with Lister on the pretext of it being an effortless way for his body to undergo some disciplined exercise and dieting... and promptly overindulges in everything he had been denied since his digital resurrection, putting on several pounds instead. Eventually only being stopped by his own terrible piloting... though he still had at least one go at "borrowing" the Cat's body afterwards.
 * Not to mention (female) officer Brown's reaction at being ported into the distinctly unladylike Lister in the opening minutes of the same episode, despite the grave danger that prompted the swap...
 * Rimmer gets another (brief) moment of this at the end of "Timeslides", when changing the past eventually changes everything back to normal except that he is now somehow alive. It doesn't last long.
 * Red Dwarf in general seems to love this kind of idea - a very pure, if inverted form of it must be the Emohawk, which has no emotions of its own and actually feeds by stealing others' moods and feelings (a rather particular type of sense, to be sure, - luckily none of them had their sense of humour stolen).
 * "Urgo" from Stargate SG-1. The first thing he did was overstimulate SG-1's taste buds. It caused Teal'c to drink an entire pot of scalding hot coffee, and the whole team to gorge themselves on desserts from the cafeteria.
 * "I want to live! I want to explore the universe and I want to eat pie!"
 * The characters from 3rd Rock From the Sun were like this in the first few episodes. Sally's reaction to her first sneeze, for example, seems almost orgasmic. Hilarity Ensues when she tries to figure out how to trigger more.
 * The aliens from First Wave, downloaded as they were into vat-grown human bodies as the initial part of their invasion, quickly figured out that sex in human form was somewhat more satisfying than in their original bodies, where sex was painful and thus only for procreation.
 * Angel has been a vampire for centuries. When he is temporarily turned human again he rediscovers the joys of food, tearing through the contents of the office fridge.


 * Played with in a similar way in the opening scenes of the 2010 series of Doctor Who, where a freshly regenerated Eleventh Doctor finds himself dealing not merely with the "new teeth" experienced by Doc Ten, but strangely reconfigured tastebuds. After convincing the strangely independent 8-year-old girl he meets to cook him a multitude of different foods and spitting most of them out in disgust (including a simple apple), he settles on... Fish-fingers with Custard, as his new favourite food. It doesn't hurt that the character is seemingly in pretty much a constant state of Sense Freakery just from still being alive, though.
 * The Observers from Fringe seem to have massively dulled senses of taste in comparison to a regular human, requiring massive amounts of spices just to bring it to a level they can register.
 * In a rare human example, Davis from Corner Gas is revealed in one episode to have lost his sense of smell as a child. He gets it back during the episode and goes a little nuts with it.

Tabletop Games

 * Slaanesh in Warhammer and Warhammer 40000 is a God of this. In a Cosmic Horror kind of way.
 * Slaaneshi followers tend to have their senses dulled out by constant exposure to all kinds of stimulation, forcing them to commit more and more extreme thing to be able to feel anything. Probably the ultimate expression are the Noise Marines from 40k, who use devastating sonic weapons because anything less loud won't even register to them anymore. In older versions of the models these were modified electric guitars.
 * Vampires in the Vampire: The Masquerade and Vampire: The Requiem can't eat or go out in the sun. While they like to mope about it (or not), those who have the Disciplines necessary to posses people or animals become possession freaks. Spending days or weeks on end possessing a host to experience all the living pleasures denied to them until they either kill the host from overindulgence/imprudence (and get a new one) or starve themselves.
 * There's also at least one Bloodline which is based entirely around having the power to eat and drink.
 * And then there are the strix, who are believed to be the source of the Beast that nags at the back of Kindred minds. They have the ability of possess humans as well as vampires in torpor. Once upon a time, their purpose was to make sure that Kindred (especially the humane ones) suffered, but after Rome (and with it, the vampiric government of the Camarilla) fell, their purpose slowly drifted, to the point that all they care about nowadays is experiencing everything a body can provide. And sometimes it's really hard to tell which driving ethos is scarier...
 * In Unknown Armies, possessing demons are actually dead human souls who come back and take over living humans because of an overpowering desire to experience the pleasures of physical existence again. If they were a bit monomaniacal even while alive, they're likely to go completely over the top; e.g. a demon who was an alcoholic while alive is likely to drink his host body to death in short order.
 * Dungeons and Dragons, with its many monsters, has several expressions of this trope. Perhaps the best is the Shadar-kai, which in 3.5 were a race of Fey who unwillingly tied themselves to the Plane of Shadow. To avoid fading away into nothingness, they constantly sought extreme sensations to stimulate them, though like followers of Slaanesh their actual ability to feel was degraded. Traditional "tools" for this purpose include the charming Gal-Ralan, spiked bracers of 'cold iron', a metal that pains Fey with its mere touch, which mount the spikes inside the bracers. Yes, you read that right; they drive a dozen spikes, six up, six down, all the way through each arm. In 4th edition, they were originally planning to reuse this, but they've instead gone for more of a Cenobite theme.
 * The boggarts in the Magic the Gathering setting Lorwyn are "addicted to new sensations" and will do all sorts of strange and dangerous things just to discover what they feel like. There's even a card called Sensation Gorger.
 * In the Earthdawn and Shadowrun series (which are connected), dragons are said to occasionally spend time shapeshifted into humans or other similar races (just as human magicians can shapeshift into animals). While often this is done to be able to go undercover in a way that a 50-foot reptile can't, at least one has remarked on the lovely-sensitive version of touch that we have. Dragons have vastly superior sight, hearing, smell, and taste, but all those super-armored scales get in the way of fine tactile sensation. The Great Dragon Vasdenjas even admitted that this applies to the "romantic arts," a concept which entirely squicked his ghost-writer.
 * The Society of Sensation, aka the "Sensates", from the Planescape campaign setting. Their entire ethos is based around the fact that they live in a physical universe, and the only way to enlighten/fulfill yourself is to go out there and experience and sense as much of it as you possibly can in your lifetime. Furthermore, Sensates tend to carry items called "sensory stones" that record the sensations they encounter. This allows other sensates to vicariously re-live the sensation merely by touching it. They have entire libraries' worth of these stones, for perusal by their faction members.
 * Despite that, they're not The Hedonist, and have a very specific plane where they dump members who join up only to focus on pleasurable sensations.

Video Games

 * In Dragon Age Origins this what drives all Demons to attempt Demonic Possession. They want to experience mortal life and indulge in the emotions they are aligned with such as Rage, Sloth, Hunger, Desire, or Pride. It doesn't always turn out so well if they get stuck in less than ideal hosts, such as corpses or trees.

Webcomics

 * Caliban the demon on Narbonic.
 * The very thing that drives Warp-Aci in Dan and Mabs Furry Adventures to bind themselves to and serve a human host, just to be able to exist on the main characters' plane of reality, which appears far more interesting and colourful than whatever mysterious limbo they come from. The experience seems to overload their ability to focus quite often, though, and their tendancy to eat anything small enough to fit in their (usually-absent!) mouths can cause considerable trouble. They don't actually need to eat, but they seem to greatly enjoy the taste and sensation; anything they consume is not digested but teleported to a random but fixed location. In the case of Fi, Dan's Warp-Aci, this is ).
 * Treated with unexpected restraint and even Deconstruction any time a character is transformed or otherwise experiencing uncommon senses in El Goonish Shive, given the comic's obsession with transformation, half-alien multi-forming sentients and Gender Bending, and having both a gentleman pervert Mad Scientist, inquisitive semi-Straw Feminist, gender-switched clone-twin (who once thought herself doomed to a very short life and, after that, permanently hit with the First Law of Gender Bending stick) AND various mischevious demons. The few times direct experiences of new sensations are mentioned, they appear to either be quite painful (Elliot's cat-boy form), embarrassing/awkward (the whole "Party" arc), or simply underwhelming (Susan's experience of the party). Except for the first time we see Tedd transformed... but even that's off-frame and all we know for sure is he was posing in the mirror rather than doing... er, anything else...
 * Nancy of Ow My Sanity has developed quite a taste for breakfast food. Interestingly, the very concept of "liking" anything is new to her as well.
 * Archipelago: After Raven  he starts a journal of everything he eats, detailing how much he likes it. He works through is meals quite slowly (Unless he's eating cake).
 * In Northwind, Tiel and Iax are two fallen angels who experience hunger for the first time upon being banished to Earth. When they enter a fast-food restaurant, Tiel comments, "If eating's like smelling, I can see why humans like doing it so much!" Iax steals another customer's food, and Tiel proceeds to bite into a still-wrapped burger, at which he says, "The outside is waxy and tough, but the insides are really tasty!"
 * Homestuck: Terezi is an odd case. After losing her sight, she gained the ability to taste and smell colors to compensate, and now she's driven wild by the taste of colors. Her own house is decorated with a delicious mishmash of garishly clashing hues, and when she enters the Sgrub game as Karkat's server player, she starts slapping paint all over his house as well. At least part of the reason why she likes Dave so much is because he types in red, her favorite color/flavor.

Web Original
"Have you ever felt the motion of water being poured into your three dimensional organs? I have, and it is miraculous."
 * 3D Lee in Kickassia, after a brief initial moment of Badass, spends the rest of the special in enraptured awe of the amazing sensations that three-dimensional video existence enables, compared to existence as a series of still 2D photographs.

Western Animation

 * Parodied relentlessly in Futurama in the What If story, quoted above, where Bender is transformed into a human. After tasting food (and drinking beer and smoking - and throwing up) for the first time, it was just such an instant shock that he couldn't stop eating and ended up a horrifying humanoid blob that weighed 900 pounds and could barely move -- after only a week! Then he died at a party in his honor.
 * There's also the Freaky Friday Flip, where he switches bodies with Amy, and as he swims to the Robo-Hungarian emperor's yacht, he complains, "Stupid air-needing lungs."
 * While she was an Energy Being possessing a human, and not transforming into one, the Phoenix Force in the 'X-Men cartoon fits this trope to a T; after possessing Jean Gray to fulfill her duty to protect the M'Krann Crystal, the cosmic entity became duly aware of the human senses she now had access to, becoming addicted to them and opening herself up to be manipulated by an evil BDSM mutant group (no, seriously) and turning evil, herself. She was only stopped after Jean had been killed, cutting the Phoenix Force off from the mortal's senses and reverting her back to her normal self.

Real Life

 * Truth in Television, babies love to put stuff in their mouths and stare at stuff.
 * This troper, who has experience working with children who cannot eat by themselves and require tube feeding, has found that these children tend to react very positively to sweet flavors like orange juice or cherry chap stick when given the opportunity to taste them.
 * Being on ecstasy generally turns people into gluttons for sensation, especially touch. The drug doesn't change how much sensation you're physically capable of perceiving, so this is a nonstandard example, but it does make your brain filter out less of that sensory input and therefore the effects are similar.
 * Note that it isn't universal; your sense of taste and smell are rendered almost null compared to sight/sound/touch, as is common with many other stimulants or psychadelics such as LSD. The urban legend persists of a boyfriend dumping his girlfriend after having incredibly intense sex with her on ecstasy, it never being the same afterward.
 * Marijuana, however, is famous for heightened your sense of taste, i.e. The Munchies.
 * The berries of Synsepalum dulcificum (usually called Miracle Berries) have glycoproteins that bond with the taste buds that detect sour flavors, making it so sour foods taste sweet for around half an hour. Some people have started organizing "flavor-tripping" parties to sample as many different kinds of foods as possible while the effects last.
 * Can happen to smokers who quit, since they often have their sense of smell/taste deadened a lot and it returns after quitting. Of course this can also lead to Fridge Horror when they discover what other smokers can smell like to a nonsmoker...