N100, N200, and P300 Auditory Event-Related Potentials Depending on Handedness and Response Tasks such as Button Pressing and Mental Counting

Purpose: This study was to determine the effects of response tasks, such as button pressing and mental counting, and handedness on N100, N200, and P300 auditory event-related potential (AERP).Methods: A total of 50 normal-hearing young adults with the average age of 21.6 (±1.5) years participated in this study. Among them, 15 men and 15 women were right-handed and 10 men and 10 women were left-handed. An oddball paradigm was used to deliver 30 stimuli of 2 kHz target tone bursts and 120 stimuli of 1 kHz nontarget tone bursts. The stimuli were presented at 70 dB sound pressure level with the rate of 1/s.Results: The button pressing task elicited significantly smaller N100 and larger P300 amplitudes than the mental counting task. N200 latency was significantly lower and P300 amplitude was higher in left-handed participants than those who are right-handed. Appearance percentages of right-/left-handed participants for N100, N200, and P300 were 80/95%, 85/85%, and 75/75% for the button pressing task and 80/90%, 80/80%, and 70/70% for mental counting task, respectively.Conclusion: The significant difference in appearance percentage between response tasks supported that P300 was a strong endogenous potential. N100 and N200 were thought to have both endogenous and exogenous characteristics. A more sensitive approach in selecting the task of response for the target stimuli and careful consideration for the handedness is necessary for AERP recordings.

The Development of Counting Strategies for Single-Digit Addition

Over 9 months, structured clinical interviews with 17 kindergartners were used to study (a) the learning of a concrete counting strategy for addition, (b) the transition from concrete to mental counting strategies, and (c) the role of the commutativity principle in developing more economical counting strategies. Kindergartners appear to differ in their readiness to use a concrete strategy. Many children persisted in counting all with objects. The most common sequence of mental counting strategies was counting all starting with the first addend, counting all starting with the larger addend, and then counting on from the larger addend. A knowledge of commutativity does not appear to be necessary to invent counting strategies that disregard addend order.

Rehearsal of Temporal Visual Information

This study compared the short-term retention characteristics of temporal information when subjects experienced time under either subject-defined or experimenter-defined rehearsal. Subjects were presented visual durations of 1 and 4 sec. and then required to reproduce these durations following a 15-sec. retention interval. To help maintain the durations in memory, subjects were asked to use either a conscious cognitive strategy or a mental counting strategy. It was predicted that experimenter-defined rehearsal would show less forgetting, as measured by variable error, but this prediction was not supported. There also was no evidence of any response bias or context effects in the temporal reproductions. These results were compared with two previous studies that utilized similar cognitive strategies.

Immediate Reproduction of Temporal Information under Four Cognitive Strategies

The main purpose was to determine the retention characteristics of temporal information when subjects experienced time under a retention interval of immediate reproduction and various cognitive strategies for time estimation. Four levels of cognitive strategy were used, viz., conscious, mental counting, counting aloud without auditory cues, and counting aloud with auditory cues. The latter three cognitive strategies were experimenter-defined, time-aiding techniques. Subjects were instructed to refrain from employing time-aiding techniques under a conscious cognitive strategy for time estimation. Visual durations of 1, 2, and 4 sec. were estimated by 12 subjects under the method of reproduction. Two measures of performance were computed, viz., variable and constant errors. The general conclusions were: (a) the effectiveness of mental counting, counting aloud without auditory cues, and counting aloud with auditory cues as cognitive strategies over conscious cognitive strategy in terms of variability depends on the duration used, and (b) in terms of accuracy and variability an increase in the number of cues under time-aiding techniques does not necessarily produce better performance.