I'm going to go deeper into spider sense because it needs explaining. Spiders have no spider sense. They have cilia in there skin that allow them to feel subtle vibrations on webbing. If there is any animal that has a 360 degree view, it is a fly because of their eye's structure. Being that spiders can only feel vibrations like these through the air, their web, and by actual touching, and due that peter wears clothes that would suppress the cilia from feeling anything, I doubt entirely that it is a "spider sense" at all.
Introduce peter the nerd. This kid has been picked on since birth. Bullies punch him, he is a smart mouth as a nervous twitch, and he has been given reflexes from the spider. If he had been infected by a virus that increased his reflexes and gave him a spider's predatory instincts, I could see a hyperactive adrenal system activating whenever he hears something that would indicate that he is going to be beat up.
Now if anyone here has heard of Pavlov, you know what I'm talking about. Pavlov was a scientist that played a bell, every time he fed a dog. One time, he played the bell, and the dog salivated like he was eating.
Another scientist shocked rats every time he played a tone. The scientist played the tone, and the rat freaked out like he was being shocked.
Now peter has been beat up since he was a kid. Everyone "telegraphs" their fights long before they fight. It's basic physiology. In every martial art, people have to breathe while they punch, they step into the ground when the prepare a punch. Peter knows these telegraphs. He's been exposed to them since he was little.
Now let's pretend that peter was like that rat. He hears the grunt, the slamming of the doors, and the thumping on the shoes. This becomes the tone that shocks his immune system. Like usual, his body pumps him with adrenaline that says you're about to be punched. Now the difference now is that he has stronger nerves due to the spider's virus.
In the comics, flash is the one that hurts him the most. By his stance, we can judge him as a boxer. Peter's knowledge of flash allows him to know he will be punched. His subconscious tells him to dodge.
Adrenaline is how he does these things. Symptoms include slowed time, increased strength, pain resistance, faster muscles, and the ability to hear and hyper focus on everything around him.
My final piece of evidence that supports (though not proves) my theory is the symbiote.
In all media outlets where peter is infected with the symbiote, he goes to sleep, he is suffocated, and he wakes upside down looking at glass. Wait, how is that possible? If the spider sense is a psychic power, or due to vibrations, how come peter didn't wake up? He will wake up when he hears the green goblin's glider, but not when the symbiote is crawling on him? We can't use that excuse that when the symbiote bonds to peter, he can't sense it. That would only occur after the symbiote bonded to him.
The reason he didn't wake up is because he's not gifted with a super sense, it is because he was conditioned to get an adrenal response when he hears a tone that tells him that he's about to get hurt. That's why he didn't wake up when he was about to be choked to death in his sleep. It's because the symbiote was silent. Peter's mind and body hadn't deemed it a threat.
Finally, there is a manual that explains all of spiderman's powers: It's a work of fiction, but it will serve your purpose fine. It suggests that spidersense is a form of meditation that you can train. It also goes into climbing, and, well, just check it out.
http://www.amazon.com/The-Spider-Ma...UWZI/ref=sr_1_1?ie=UTF8&qid=1333945563&sr=8-1
