The opposite of "un-noticing" refers to the act of being acutely aware of one's surroundings or paying attention to something. Synonyms for this could include "observant," "attentive," "perceptive," or "mindful." Each of these words suggest a heightened state of consciousness and a deliberate effort to remain present in the moment. Conversely, if one is "un-noticing," they may be described as "oblivious," "unobservant," or "unaware." These words suggest a lack of interest or attention to detail, and may be seen as negative qualities when it comes to being mindful and present in one's environment.