BACKGROUND: Paradoxical kinesis has been observed in bradykinetic @entity1 with @entity191 . Paradoxical kinesis occurs in situations where an individual is strongly motivated or influenced by relevant external cues. Our aim was to induce paradoxical kinesis in the laboratory. We tested whether the motivation of avoiding a mild @entity1457 was sufficient to induce paradoxical kinesis in externally-triggered and self-initiated conditions in @entity1 with @entity191 tested on medication and in age-matched controls. METHODS: @entity1 completed a shock avoidance behavioural paradigm in which half of the trials could result in a mild @entity1457 if the @entity1 did not move fast enough. Half of the trials of each type were self-initiated and half were externally-triggered. The criterion for avoiding shock was a maximum movement time, adjusted according to each @entity1 's performance on previous trials using a staircase tracking procedure. RESULTS: On trials with threat of shock, both @entity1 with @entity191 and controls had faster movement times compared to no potential shock trials, in both self-initiated and externally-triggered conditions. The magnitude of improvement of movement time from no potential shock to potential shock trials was positively correlated with @entity148 ratings. CONCLUSIONS: When motivated to avoid mild @entity1457 , @entity1 with @entity191 , similar to healthy controls, showed significant speeding of movement execution. This was observed in both self-initiated and externally-triggered versions of the task. Nevertheless, in the ET condition the improvement of reaction times induced by motivation to avoid shocks was greater for the @entity1726 @entity1 than controls, highlighting the value of external cues for movement initiation in @entity1726 @entity1 . The magnitude of improvement from the no potential shock to the potential shock trials was associated with the threat-induced @entity148 . This demonstration of paradoxical kinesis in the laboratory under both self-initiated and externally-triggered conditions has implications for motivational and attentional enhancement of movement speed in @entity191 .

Motivational Modulation of Self-Initiated and Externally Triggered Movement Speed Induced by Threat of Shock: Experimental Evidence for Paradoxical Kinesis in XXXX .

@entity1 :: ('9606', 'Species') :: ['patients', 'participant', 'Participants', 'people'] @entity1457 :: ('MESH:D012769', 'Disease') :: ['electric shock'] @entity191 :: ('MESH:D010300', 'Disease') :: ["Parkinson's disease"] @entity1726 :: ('OMIM:168600', 'Disease') :: ['PD'] @entity148 :: ('MESH:D001008', 'Disease') :: ['anxiety']
@entity191 :: (MESH:D010300,Disease) :: ['Parkinson's Disease']
