Dissociating cognitive and motor interference effects on kinesthetic short-term memory

Abstract

In two experiments, we investigated how short-term memory of kinesthetically defined spatial locations suffers from either motor or cognitive distraction. In Exp. 1, 22 blindfolded participants moved a handle with their right hand towards a mechanical stop and back to the start and then reproduced the encoded stop position by a second movement. The retention interval was adjusted to approximately 0 and 8 s. In half of the trials participants had to provide a verbal judgment of the target distance after encoding (cognitive distractor). Analyses of constant and variable errors indicated that the verbal judgments interfered with the motor reproduction only, when the retention interval was long. In Exp. 2, 22 other participants performed the same task but instead of providing verbal distance estimations they performed an additional movement either with their right or left hand during the retention interval. Constant error was affected by the side of the interpolated movement (right vs. left hand) and by the delay interval. The results show that reproduction of kinesthetically encoded spatial locations is affected differently in long- and short-retention intervals by cognitive and motor interference. This suggests that reproduction behavior is based on distinct codes during immediate vs. delayed recall.

ERP correlates of linear hand movements in a motor reproduction task

“…As in our previous study using a similar experimental setup, in which the reproduction of kinesthetically defined spatial locations was required (Kirsch, Hennighausen, & Rösler, 2009), we observed results deviating from previous findings for selected movement parameters. In contrast to an increase in endpoint variability with movement distance that typically occurs in unrestricted movements, we here obtained an opposite pattern: The variable error decreased with distance.…”

“…Accordingly, distance differences found during both movement phases were similarly pronounced in all delay conditions and were independent from the delay manipulation. This fact does not necessarily speak against distinct sensorimotor mechanisms involved in short and long delay conditions (see, e.g., Kirsch et al, 2009) and may possibly indicate distinct motor planning rather than control processes (see, e.g., Figure 1 for different DC drifts prior to the reproduction movement). Because of space reasons, we discuss in the following only the distance effects.…”

Facilitating the Use of Online Visual Feedback: Advance Information and the Inter-Trial Interval?

“…In addition to above-mentioned work arguing for decays in visual representation (e.g., Binsted et al 2006;Elliott and Madalena 1987), the gradual increase in error in NV trials could be also due to a weakening proprioceptive representation. Research by Kirsch, Hennighausen and Rösler (2009), previously found that when individuals performed a movement to a remembered proprioceptive target, they were relatively accurate for up to 8 s following the previous movement-which approximately coincides with the 2nd NV trial in our experiment (see also Desmurget, Vindras, Gréa, Viviani and Grafton, 2000). Nevertheless, compared with the results of Cheng et al (2008), individuals relied significantly on available real-time visual feedback to control their movements with the 5 s ITI.…”

“…Further, it is important to note that visual and proprioceptive representations may decay at different rates. Specifically, decays in memory representation-perhaps based on proprioceptive information-can be observed more than 8-10 s without visual feedback (Bowditch and Southard, 1882;Desmurget et al, 2000;Kirsch et al, 2009). Lastly, the above comparisons between Cheng et al (2008) and this study must also be made with caution.…”

Perceptual and behavioral adjustments after action inhibition

“…When blindfolded participants were asked to move a handle rapidly until it was mechanically stopped and to reproduce that stop position through another unrestricted movement, they tended to slow down the reproduction movement when the initial movement was interrupted shortly after its onset (see Kirsch, Hennighausen, & Rösler, 2010, Table 1). Interestingly, when the task required a verbal estimate of the movement distance before reproduction, participants substantially underestimated the distance in those conditions (i.e., when movements were stopped shortly after their onsets; Kirsch, Hennighausen, & Rösler, 2009). Thus, a decrease in subjective distance (after movement interruption) appeared to precede a slower (reproduction) movement.…”