I found that the feeling is most dramatic when the avatar enters a small enclosed space and it is difficult to find an exit. Making everything the same flat colors, with few shadows, makes it difficult to understand spatial cues when moving the camera around such a space. Second Life's unique camera system, where whatever you click on becomes the pivot point, contributes its own problems, especially if you accidentally click on the outside of the enclosure so that you can't easily maneuver back inside. Discomfort increases the longer this goes on.
In the virtual environment, claustrophobia is heightened by confusion and frustration when the viewer encounters inconsistent patterns, where boundaries between objects are unclear, and navigational directions are ambiguous. This is evidence of the extent to which a human will interface with a cyber body. When the "controls" linking the human mind to the virtual representation malfunction, it often feels as though the individual is being physically constrained.