Stimulus-response dimensional overlap elicits a decreasing Simon effect along the vertical dimension / A sobreposição dimensional entre o estímulo e a resposta na dimensão vertical provoca um decaimento do efeito Simon / Superposición dimensional induce la disminución del efecto Simon en la dimensión vertical

In Simon task, the response is faster when stimulus and response locations are spatially correspondent than when they are on opposite sides (Simon effect - SE). The SE was found with both horizontal and vertical stimulus-response arrangements. The horizontal SE decreases as reaction times increase. In contrast, the vertical SE does not decay over time. In this work, we investigate the vertical SE when both stimuli and responses are located along the vertical dimension. Results showed a decreasing SE occurring along the vertical dimension suggesting that similar underlying mechanisms may be involved both for the horizontal and vertical Simon effects.

Na tarefa de Simon, a resposta é mais rápida quando os locais do estímulo e da resposta são espacialmente correspondentes do que quando estão em lados opostos (efeito Simon - ES). O ES foi observado ao longo das dimensões horizontal e vertical. O ES horizontal diminui à medida que aumenta o tempo de reação, o que não ocorre com o ES vertical. Neste trabalho, investigamos o ES vertical com estímulos e respostas localizados ambos ao longo da dimensão vertical. Os resultados mostraram um ES decrescente na dimensão vertical sugerindo que mecanismos semelhantes estão envolvidos nos efeitos Simon horizontal e vertical.

En la tarea de Simón, la respuesta es más rápida cuando el estímulo y la respuesta son espacialmente correspondientes que cuando están en lados opuestos (efecto Simon - ES). La ES se observó en las dimensiones horizontal y vertical. El ES horizontal disminuye con el aumento del tiempo de reacción, lo que no ocurre con ES vertical. En este trabajo, se investigó el ES vertical con estímulos y respuestas situadas en la dimensión vertical. Los resultados mostraron una disminución del ES en la dimensión vertical lo que sugiere que mecanismos similares están implicados en los efectos Simon horizontal y vertical.

Left-right judgment of haptic stimuli representing the human hand

The handedness recognition of visually perceived body parts engages motor representations that are constrained by the same biomechanical factors that limit the execution of real movements. In the present study, we used small plastic cutouts that represented the human hand to investigate the properties of mental images generated during their haptic exploration. Our working hypothesis was that any handedness recognition task that involves body parts depends on motor imagery. Forty-four blindfolded, right-handed volunteers participated in a handedness evaluation experiment using their index finger to explore either the back or palm view of a haptic stimulus that represented the human hand. The stimuli were presented in four different orientations, and we measured the subjects' response times. Our results showed that stimulus configurations that resemble awkward positions of the human hand are associated with longer response times (p < .006), indicating that the haptic exploration of stimuli that represent body parts also leads to motor imagery that is constrained by biomechanical factors