advertence, advertency, alertness, apperception, appreciation, appreciativeness, assiduity, assiduousness, attention, attention span, attentiveness, care, cognition, cognizance, concentration, consciousness, consideration, diligence, ear, earnestness, experience, feeling, heed, heedfulness, insight, intentiveness, intentness, mindfulness, noesis, note, notice, observance, observation, percept, perception, realization, recognition, regard, regardfulness, remark, respect, response, response to stimuli, sensation, sense, sense impression, sense perception, sensibility, sensory experience, thought