Why do some people gag when someone is vomiting?

Why is it that when a person vomits, it causes others to vomit — even when they don't have an illness causing it? Is this something triggered by the brain or is it something that happens by reflex (survival instinct) for someone to vomit since, perhaps, what the first person was eating may affect the second who vomits as well?


Can our relationship survive summer break if we haven't had sex yet?

I am a 19-year-old college student and am seriously involved with my boyfriend who is a 20-year-old college student. We have even talked of getting married someday. Our relationship is very close and we talk about everything, and he is very wonderful and supportive. I feel very committed to him and would really like to have sex with him. We have tried twice, but it hasn't really worked out because my vagina is too tight. I am pretty sure the problem is just that it needs to be stretched more, because I have been to the gynecologist and don't have any infections. He says that he is okay with whatever we do and that he loves me no matter what, but I still feel guilty about not being able to go all the way. How do I get over this guilt? I will be leaving college for the summer soon and we will be separated for awhile and I want to make sure that our relationship is as solid as possible before I leave so we have the absolute best chances of surviving the summer!


Will I ever find a gay partner?

I've been gay all of my life, and until just now, I've learned to accept it. I've told all my friends that I am gay. Some of them didn't like that, and now they're not my friends. None of my other friends are gay, which was a disappointment because I had a crush on one of them. Now I don't know what to do because not only do I not know who else is gay, but I don't have the courage to ask someone out. I'm afraid that if I can't ask someone out by the time I'm out of college, I'll never be able to have a relationship. I don't want to have to resort to online dating either. I want to know how I can overcome my fear.


How do I tell my girlfriend I'm sterile?

I am an 18-year-old male. And I lost my ability to reproduce in a bull riding accident at a rodeo I competed in about two years ago. I would like to father children more than anything. And now I have a girlfriend who is talking of wanting to have kids in the future. But I can't bring myself to tell her that I can't because I still haven't dealt with the problem of coping with it myself. I need to know how to deal with the fact I cannot have kids, especially now that my significant other wants them, but is ignorant to the fact that I am sterile. Please help me ASAP! This is tearing me apart.


Will past experimentation with drugs lead to permanent brain damage?

I have a history of "experimentation" (infrequent or occasional use of ecstasy, 'shrooms, and other drugs — mostly prescription pills). I am completely sober now, but am worried about long-term damage to my brain. I used drugs infrequently (no more than three to five times for each substance), but drank regularly. How worried should I be? Is there anything I can do to combat long-term effects?


Is neck and back cracking all it's cracked up to be?

1) I read the information on your website about knuckle cracking, and I was wondering if it applies to cracking backs and necks. I know that people often have their backs cracked by friends, etc. because it feels good and seems to relieve tension. Also, when my neck feels tight, I often turn it from side to side until it cracks and feels better. I've heard that chiropractors do some version of this, and call it "realignment." Is this safe? Is there a right or a wrong way to crack a back or neck? Is cracking your back/neck actually therapeutic in some way?

2) As a college student, I sometimes spend long hours reading books or looking at computer screens, and often my neck gets stiff. Like many of my joints that get stiff, sometimes I crack my neck, like I would crack my knees or fingers when they feel stiff. I often wind up doing this several times a day.

My question is, could I do irreparable damage to my spinal system if I continue using this method to soothe a stiff neck? Could I wind up a paraplegic if I continue to crack my neck? Leak spinal fluid, etc.?