Yes, but be aware of the “substantially gainful activity” (SGA) requirement. If you can earn more than $1,070 per month (gross) when you apply for SSI and SSD benefits in the Portland area, you will be considered capable for SGA and therefore not disabled. The idea is that your health conditions have not risen to the level of “disability” if you can earn at least that much.
Part-time jobs, short-term jobs, and work that earns you less than $1,070 per month are less likely to affect your claim. Be cautious about extensive volunteering or any work-like activity which could (if paid) earn you more than that amount.
SSDI recipients are entitled to test their ability to work and continue to receive full benefits regardless of whether they make more than the SGA amount, for a nine-month trial work period. For 2014, the SSA considers any month where a person has a monthly income of more than $770 a trial work month.