There are some types of uncertainty with which I do well (lab project outcomes). Other types of uncertainty (did I choose the right graduate program) highlight the fomentation of anxiety at which I excel.
I have read that this is a common after-effect of deciding on a program, or a post doctoral or even faculty position. The additional consideration that I am entering this with a much more specialized background than most students (read: 4 years in a lab where I introduced, managed and wrote manuscripts for my own projects) puts the anxiety into perspective.
I have chosen an excellent program, with a handful of outstanding mentors and a supportive student populous; and in it, I will thrive.
My particular mental block comes from peering (possibly, too) far into my future. Research, for me, will always be most exciting in the world of repairing neurodegenerative pathologies that lead to motor dysfunction. Ideally, Parkinson's and Huntington's diseases. But there are also technical skills hovering in my dreams that I can only learn (in my chosen program) in spinal cord injury research.
This is perfectly adequate in terms of developing interventions for motor impairments. However, it presents a confound to the seamless progression of my academic career. Namely, if I transition from the basal ganglia (PD and HD, where I have spent the last four years) to the spinal cord, I risk limiting my future post doc positions to spinal cord labs.
Had I the resources, I would present the stats on graduate students who obtained post doc/ faculty positions in a different sub-field of neuroscience than their graduate studies... For the time being, I will attempt to resolve my inner conflict with the hope that it will all settle itself when I get there.