PhD in Neuroscience- Rec Letter Choices

[tama5tchi]

Hello!

I'm an M.S. student looking to apply for Ph.D. programs in neuroscience. A lot of the schools I'm looking into asks for 3 academic recs and I'm having a bit of a struggle trying to figure out who to ask for the letters. I heard that for rec letters I should get them from PIs or lab supervisors in the research you're involved in, but I was wondering if I can also ask professors that you've had as well. Also, I recently became a co-author for a research paper for a lab I was involved in college. Would the schools mind if I ask someone from undergrad for rec letters? 

[PokePsych]

I've had both past and present supervisors/advisors in the bunch. Think it really matters on who can comment best on your skills/personality/aptitude/anything else that qualifies you. I've had a prof I worked closely with in Undergrad write me a letter and two profs I worked with in my Masters. I think you should ask people who know you well and who have for sure something nice to say about you