Final answer:
Disintegration is the stage of cultural adaptation characterized by nervousness and insecurity, as part of the culture shock experience. It reflects the stress and disorientation felt when facing different customs and social norms in a new culture.
Step-by-step explanation:
The stage of cultural adaptation characterized by feelings of nervousness and insecurity, because things are so different and strange, is known as disintegration. This stage typically follows the initial excitement of entering a new culture, where the individual starts to experience culture shock.
At this point, the differences between the new culture and the individual's native culture become more pronounced, leading to stress and disorientation. Challenges such as language barriers, different customs, and social norms increase the sense of incompetence and insecurity. Over time, with increased understanding and adaptation to the new environment, individuals typically move past this stage and begin to integrate more smoothly into the host culture.