Answer: Cataplexy
Explanation: Cataplexy could be described as a muscle weakness or paralysis experienced without a loss of consciousness, however such person will be unable to move as the muscles seems to have become redundant at the moment. The causes of Cataplexy has been attributed to actions or scenes which evokes strong emotion or excitement. Tim's experience of Cataplexy which lead to muscle weakness without a loss of conciousness could most likely be trigerred by fear, anxiety or stress of presenting his most recent work to the audience in the night slam poetry group.