The brief article refers to recent research by Jan Kaminski et al published in Nature online in February 2017. The research has found that short term memory relies on what are termed ‘persistently active neurons’, neurons that stay active for a few seconds, ie the amount of time that the recalled memory itself stays alive. Such neurons were found in both the medial frontal lobe and the medial temporal lobe.
Link to article: https://biotechin.asia/2017/02/22/scientists-identify-brain-processes-that-are-involved-in-creating-and-maintaining-short-term-memories/