I've always had this very strong attitude that if I am responsible for something - a task in a project management system, a service, a domain, a class, whatever - I own it and understand the problem and chase what's needed in case it needs some clarification. I'll dig the code to find what's needed to be modified/added/removed and apply the changes, usually submitting the change for review and wait for feedback.
I am not fond of the idea of another team member making changes that are related to what I'm working on - i.e. submitting code on a task that I explicitly asked for review. I don't do that and I find disrespectful.
Instead I much prefer to have the team member sit with me so we can work together and change whatever was deemed necessary or missing.
I also try to be as approachable and open as possible towards other team members but never offering advice where not required and also don't really like eavesdropping - I think it's disrespectful but, at times, it can be useful.
Totally understand and agree that code bases have a shared responsibility but keen to hear what other people are doing and how you work with other team members.
edit: title