Starbucks officially released its beloved pumpkin spice latte--or PSL, for true fans--for the season earlier this month, kicking off a new round in what has become a $361 million flavor market. If lattes aren't your thing, don't worry. You can find pumpkin spice cookies, candy, popcorn, ice cream, bread, yogurt and just about anything else that floats your boat. And it turns out, there's some real science and psychology behind why you can't get enough.

1. There's salt in the recipe.

Salt is a natural flavor enhancer that brings out specific notes of a dish or drink. Even though you (correctly) might associate lattes and other pumpkin spice products with sugar, companies often include decent amount of salts that make the overall taste better, too. Starbucks' 16-oz latte, for example, has 10 percent of your recommended daily allowance. Because salt enhances flavors, it makes your treat taste even sweeter and more decadent. This "flavor layering" also prevents your brain from experiencing sensory specific satiety, meaning your brain doesn't get bored with the overall flavor the way it would if you just had the salt and sugar individually. Your brain also responds to salt because it is an essential nutrient your body needs. In fact, researchers believe it stimulates the brain much like cigarettes and hard drugs do.

2. You get a sugar and fat combination.

3. Caffeine stimulates you.

Caffeine is chemical that occurs naturally in coffee beans and other substances like tea. It is a stimulant that inhibits adenosine in the brain and, subsequently, makes you feel alert and focused. A 16-oz pumpkin spice latte from Starbucks has 150 milligrams of caffeine. This is well below the Mayo Clinic's recommendation of 400 milligrams per day for adults and is perfectly safe, but it's still enough to feel more energized as you sit through a meeting (or go play in the leaves). Caffeine is also addictive, so you might come back for a second latte just so you don't go through withdrawal symptoms, which can occur on daily doses as low as 100 milligrams.

4. You just want to fit in.

See everybody else in that Starbucks line? You don't want to be the loner, do you? The outsider? Of course you don't. So you buy your pumpkin spice because everybody else is doing it and you don't want to take the risk of being ostracized. It feels good to be a groupie!

5. Spices make you remember nice times (but also protect your health).

Emotional recall in the brain is very closely tied to other senses, especially smell. And for most people, the memories associated with nutmeg, cloves and cinnamon, the key spices in pumpkin spice, are good ones. Every time you tip your coffee cup, you trigger the recall of events that warmed your heart, so you feel uplifted. And as a bonus, Harvard Medical School asserts that these spices are associated with benefits like improved memory, increased attention, enhanced cognitive processing, improved mood, pain relief, inducing sleep and antibacterial/antioxidant/antimicrobial properties.

6. It's just for a limited time.

Some pumpkin spice products technically might be available through the year, but overall, they're promoted as being around only for a few days or weeks. If you don't act fast, marketers tell you, you'll miss out. Fear of missing out can cause you to reach for your wallet all by itself, tying to the desire to fit in. But reactance theory also says that, if you know something is available just for a limited time like this, you'll view the product as more appealing. This has to do with the fact that the "limited time" nature of the offer threatens freedom of behavior (purchase). Buying the item makes you feel like you're still free to do what you want.