Influence of an Intertrial Interval on Sequential Effects Related to Preparatory Period Duration for Reaction Time-Task

1979 ◽  
Vol 49 (3) ◽  
pp. 979-987 ◽  
Author(s):  
M. Granjon ◽  
C. A. Possamaï ◽  
G. Reynard ◽  
D. Oberti
Keyword(s):  
Reaction Time ◽  
Time Course ◽  
Memory Search ◽  
Reaction Time Task ◽  
Rest Interval ◽  
Sequential Effects ◽  
Preparatory Period ◽  
The Moment ◽  
The Cost ◽  
Relationship Of

In reaction time tasks, where the moment of occurrence of the response signal is uncertain, the temporal constraints of preparatory processes imply that subjects distribute their preparation during the preparatory period. The notion of cost of preparation has been proposed to explain the time course of these processes. This experiment was run to determine the effect of the cost of preparation on a serial-RT task and on a RT task where a rest interval of various possible durations (3, 6, or 9 sec.) is introduced. 12 subjects were tested. Data show that the amount spent on preparation during a trial affects the subject's performance during the next trials. But an hypothesis about memory search must also be advanced to explain the effect of the rest interval on the relationship of RT and the current preparatory period.

Changing the “When” and “What” of Intended Actions

2009 ◽  
Vol 102 (5) ◽  
pp. 2755-2762 ◽  
Author(s):  
Sukhvinder S. Obhi ◽  
Shannon Matkovich ◽  
Robert Chen
Keyword(s):  
Reaction Time ◽  
Simple Reaction Time ◽  
Index Finger ◽  
Sensory Information ◽  
Motor Preparation ◽  
Warning Stimulus ◽  
Inhibitory Mechanism ◽  
Preparatory Period ◽  
The Cost ◽  
Reaction Time Condition

Humans often have to modify the timing and/or type of their planned actions on the basis of new sensory information. In the present experiments, participants planned to make a right index finger keypress 3 s after a warning stimulus but on some trials were interrupted by a temporally unpredictable auditory tone prompting the same action ( experiment 1) or a different action ( experiment 2). In experiment 1, by comparing the reaction time (RT) to tones presented at different stages of the preparatory period to RT in a simple reaction time condition, we determined the cost of switching from an internally generated mode of response production to an externally triggered mode in situations requiring only a change in when an action is made (i.e., when the tone prompts the action at a different time from the intended time of action). Results showed that the cost occurred for interruption tones delivered 200 ms after a warning stimulus and remained relatively stable throughout most of the preparatory period with a reduction in the magnitude of the cost during the last 200 ms prior to the intended time of movement. In experiment 2, which included conditions requiring a change in both when and what action is produced on the tone, results show a larger cost when the switched to action is different from the action being prepared. We discuss our results in the light of neurophysiological experiments on motor preparation and suggest that intending to act is accompanied by a general inhibitory mechanism preventing premature motor output and a specific excitatory process pertaining to the intended movement. Interactions between these two mechanisms could account for our behavioral results.

scholarly journals Reaction to a Visual Stimulus: Anticipation with Steady and Dynamic Contractions

2019 ◽  
Vol 69 (1) ◽  
pp. 17-27
Author(s):  
Agostina Casamento-Moran ◽  
Stefan Delmas ◽  
Seoung Hoon Park ◽  
Basma Yacoubi ◽  
Evangelos A. Christou
Keyword(s):  
Reaction Time ◽  
Planning Process ◽  
Dynamic Condition ◽  
Motor Planning ◽  
Reaction Time Task ◽  
Emg Activity ◽  
Time Interval ◽  
Variable Direction ◽  
The Moment ◽  
Study Participants

Abstract Reacting fast to visual stimuli is important for many activities of daily living and sports. It remains unknown whether the strategy used during the anticipatory period influences the speed of the reaction. The purpose of this study was to determine if reaction time (RT) differs following a steady and a dynamic anticipatory strategy. Twenty‐two young adults (21.0 ± 2.2 yrs, 13 women) participated in this study. Participants performed 15 trials of a reaction time task with ankle dorsiflexion using a steady (steady force at 15% MVC) and a dynamic (oscillating force from 10‐20% MVC) anticipatory strategy. We recorded primary agonist muscle (tibialis anterior; TA) electromyographic (EMG) activity. We quantified RT as the time interval from the onset of the stimulus to the onset of force. We found that a dynamic anticipatory strategy, compared to the steady anticipatory strategy, resulted in a longer RT (p = 0.04). We classified trials of the dynamic condition based on the level and direction of anticipatory force at the moment of the response. We found that RT was longer during the middle descending relative to the middle ascending and the steady conditions (p < 0.01). All together, these results suggest that RT is longer when preceded by a dynamic anticipatory strategy. Specifically, the longer RT is a consequence of the variable direction of force at which the response can occur, which challenges the motor planning process.

Behavioral deficits induced by local injection of bicuculline and muscimol into the primate motor and premotor cortex

1991 ◽  
Vol 65 (6) ◽  
pp. 1542-1553 ◽  
Author(s):  
M. Matsumura ◽  
T. Sawaguchi ◽  
T. Oishi ◽  
K. Ueki ◽  
K. Kubota
Keyword(s):  
Reaction Time ◽  
Muscle Activity ◽  
Time Course ◽  
Premotor Cortex ◽  
Reaction Time Task ◽  
Warning Signal ◽  
Emg Activity ◽  
Gabaergic Inhibition ◽  
Gamma Aminobutyric Acid ◽  
Time Task

1. The role of intracortical GABAergic inhibition in the performance of hand movements was studied in macaque monkeys while they performed two behavioral tasks: a raisin pick-up test and a visual reaction-time task. A gamma-aminobutyric acid (GABA) agonist, muscimol (MUS; 1-5 microgram), and an antagonist, bicuculline methiodide (BMI, 1-10 micrograms), were injected at various sites in the precentral motor cortex (MC), at which single-unit activity was related to the manual aspects of the performance of the reaction-time task. 2. Manual dexterity in the raisin pick-up task was severely disturbed by injections of either MUS or BMI into the hand MC. The effect was less severe after injections into the postarcuate premotor cortex (PM). 3. Performance of the reaction-time task was unstable after injection of BMI. The instability was caused by increased electromyogram (EMG) activity and by cocontractions of agonistic and antagonistic muscles of the arm during the pressing or release of the lever. 4. Reaction time was increased by injection of MUS, although the effect was temporary and decayed within 60 min. These deficits were consistent with the time course of the decrease in the total amount of EMG activity of hand muscles related to the task. As in the case of the raisin pick-up task, performance deficits were greater when MUS and BMI were injected into the hand MC and smaller when they were injected into the PM. 5. After injection of BMI, the animals gradually began to display muscle activity in response to a green warning signal that did not require a behavioral response. The muscle activity accelerated to spontaneous muscle twitches without any external stimulus, and the animals were unable to continue the task. These BMI-induced twitches were eliminated by injection of barbiturate. 6. Appropriate levels of GABAergic inhibition in the MC appear, therefore, to be important for the regulation of spatiotemporally organized ensembles of muscle activity, in particular for reciprocal contraction at the task-related joints.

Sign in / Sign up

Export Citation Format

Share Document