MAPT and amyloidosis: Thus for example, the interplay of tau or neurofibrillary change with amyloid deposition would be expected to lead to possible bidirectional effects on sleep behaviors where there is a balancing between amyloid and tau aggregation [50] that depending on the timing and distribution of these processes, may result in disturbed sleep that is manifested by time in bed or other measures such as restlessness [51] or sleep efficiency [52].