ABSTRACT
El fenómeno de la ilusión de la mano falsa (IMF) se ha propuesto como un diseño que permite discriminar procesos perceptuales a partir de entradas sensoriales multimodales. Se han reportado varias modificaciones y variables que podrían afectar la generación del fenómeno. Este estudio se planteó bajo un diseño descriptivo-correlacional del fenómeno. Se realizó el procedimiento en jóvenes (16-48 años M = 20.86 años, DE = 4.4) colombianos para replicar el fenómeno de IMF. Los sujetos se dividieron al azar en dos grupos que diferían en el tipo de estimulación (sincrónica y desincronizada). La identificación de la IMF se realizó mediante la escala reportada en múltiples estudios, mostrando que en algunas variables como la estimulación se presentaba una diferencia en el reporte de IMF (P2. X² = 5.856: p < 0.05; P3. X² = 6.655: p <0.01 y P7(X² = 4.764: p < 0.05). Otras variables como sexo y dominancia manual mostraron algunas diferencias. La escala presenta una consistencia interna aceptable (α = 0.8). Los resultados de la IMF son similares a algunos estudios pero con puntuaciones menores que en los estudios iniciales, la diferencia en cuanto al género en tareas perceptuales podría explicar gran parte de los resultados.
The Rubber Hand Illusion (RHI) has been proposed as a design which allows to discriminate perceptual processes based on multimodal sensory inputs. Several modifications and variables have been reported that could affect the generation of the phenomenon. This study was conducted using a descriptive correlational design of this phenomenon. The procedure was conducted with young Colombian individuals (16-48 years-M = 20.86 years, SD = 4.4), seeking to replicate the RHI. The subjects were randomly divided into two groups that differed in type of stimulation (synchronised and unsynchronised). Identification of the RHI was performed using the scale reported in multiple studies, showing that the RHI report had differences in some variables such as stimulation (P2. X² = 5.856: p <.05; P3. X² = 6.655: p <.01 y P7 (X² = 4.764: p <.05). Other variables, such as gender and handedness, also showed some differences. The scale has an acceptable internal consistency ( X= 0.8). The results of the RHI are similar to some studies, but with lower scores than in the initial studies. The difference in gender in perceptual tasks could explain most of the results.
ABSTRACT
Osgood developed the semantic differential to bridge the phenomena from semantics and perception, and we applied its modified version to investigate current issues in cognitive science. We used two-dimensional rather than one-dimensional space to position nominal word items, and subjected data to multidimensional scaling (MDS). In Experiment 1 (paper-and-pencil) participants judged concrete and abstract nouns on seven bipolar semantic differential scales in three perceptual modalities: visual, auditory and touch. Six months later, in Experiment 2 (computer-assisted), the same participants mapped the same ten nouns on a balanced subset of two-dimensional planes. Our findings support the hypothesis that semantic space is physically constrained. MDS over one-dimensional ratings from Experiment 1 resulted in a particular two-dimensional solution. This two-dimensional combination was very similar to one of the raw two-dimensional maps from Experiment 2. We then concluded that this particular raw two-dimensional map is highly informative, as it captures almost all differences between word items in the given set of perceptual opposites. Its informativeness proved to be robust to experimental administration (paper-and-pencil vs. computer-assisted) and scale-orientations (horizontal vs. vertical). Recent theories, such as Barsalou's perceptual theory of knowledge, capture the tradition of conceptualizing all knowledge as inherently perceptual. Our results strongly support these theories.
Osgood desarrolló el diferencial semántico para investigar los fenómenos desde la semántica y la percepción, y aplicamos su versión modificada para investigar temas actuales en ciencia cognitiva. Utilizamos dos dimensiones en lugar de un espacio unidimensional para posicionar palabras nominales y datos sujetos a escalamiento multidimensional (MDS). En el experimento 1 (papel y lápiz) participantes consideraron sustantivos concretos y abstractos en siete escalas de diferencial semántico bipolar en tres modalidades per-ceptuales: visual, auditivo y táctil. Seis meses más tarde, en el Experimento 2 (asistida por ordenador), los mismos participantes asignaron los mismos diez sustantivos en un subconjunto equilibrado de planos bidimensionales. Nuestros resultados apoyan la hipótesis de que el espacio semántico está limitado físicamente. Las calificaciones unidimensionales sobre MDS del Experimento 1 dieron como resultado una solución de dos dimensiones particular. Esta combinación de dos dimensiones fue muy similar a uno de los mapas de dos dimensiones en bruto del Experimento 2. Se concluyó que este mapa particular de dos dimensiones es altamente informativo, ya que captura casi todas las diferencias entre las palabras en el conjunto dado de los opuestos perceptuales. Esta información demostró ser sólida a la administración experimental (papel y lápiz versus asistida por computador) y las orientaciones de la escala (horizontal y vertical). Teorías recientes, como la teoría del conocimiento perceptual de Barsalou, captura la tradición de la conceptualización del conocimiento como inherentemente perceptual. Nuestros resultados apoyan firmemente estas teorías.
Subject(s)
Semantics , CognitionABSTRACT
La ecolocación es una habilidad que usaría inconscientemente la mayoría de las personas. Resulta crucial para la movilidad independiente de la persona ciega e implica utilizar sonidos autoproducidos y sus reflexiones para localizar y reconocer objetos que no se ven. Dos nuevos paradigmas han enriquecido el estudio de esta sorprendente habilidad: el del acoplamiento sensoriomotor y el de la sustitución sensorial. El primero sostiene que los sistemas perceptivo y motor constituyen procesos acoplados que requieren un insoslayable tratamiento unificado. El segundo considera que es posible ver con los oídos o con la piel en virtud de la plasticidad cerebral. En esta segunda parte se presenta la temática en el contexto teórico de la cognición corporizada y de recientes avances en neurociencias; se desarrollan además los estudios realizados en el tercer período. En esta revisión se reflejan cambios paradigmáticos en las ciencias del comportamiento y el valor científico acrecentado de la ecolocación humana.
Echolocation is an ability that can be used daily by human beings, even without being conscious of it. It turns out to be crucial to the efficient independent mobility of the blind person, an aspect that is severely affected by blindness. It implies using the information that emerges from self-produced sounds and their reflexions in order to locate and recognize unseen objects. According to the new cognitive and ecological paradigms in perception, it is believed that the primary function of the auditory system is to determinate, i.e., to localize and recognize, the characteristics of the sound source through the sounds emitted by it. Within this context, it has been very recently argued that echolocation (i.e., the ability to locate and recognize biologically relevant secondary sound sources through the information contained in the direct-reflected couple) is a variant of that general process of primary sound sources determination. Two recently established scientific paradigms have specially enriched the study of this amazing ability: the sensorimotor contingency theory and the sensory substitution perspective. The first approach claims that the perceptual and motor systems are coupling processes that demand a thoroughly unified treatment. The second approach considers that, for example, vision loss does not mean loss of the ability to see since it is possible to see with the ears or the skin. The central idea is that the information usually captured by vision may instead be captured by touch or audition, on account of brain plasticity. In this way, in echolocation (which represents a kind of 'seeing with the ears' natural sensory substitution system that is part of the human endowment) action consists of the exploratory activity that the subject carries out through self-generation of sounds and head and/or cane movements while sensation refers to certain tonal or spatial percepts related to the presence and characteristics of the objects that the subject (implicitly) learns to perceive probably as auditory Gestalts. In the first part of this article the main theoretical aspects and a revision of the studies throughout two of the three delimited periods were developed: FIRST APPROACHES (1700 - 1935) and SIENTIFIC STUDY OF HUMAN ECHOLOCATION (1940 -1980). The questions that researchers formulated during these periods were firstly concerned with discovering if blind persons actually possessed this ability, which of the sense organs was involved and which sensory stimulation was its necessary and sufficient condition. Secondly, they inquired into the scopes of echolocation and its possible underlying psychoacoustic mechanisms. The thorough investigations carried out allowed to unequivocally establishing that audition is the sensory basis of this ability and that changes in pitch are its necessary and sufficient condition. It was also demonstrated that not only blind subjects but also appropriately trained sighted subjects were able to precisely localize and recognize the characteristics of the experimental objects. In this second part, we present the object of study within the context of theories of embodied cognition and recent developments in the field of the neurosciences; we also elaborate upon studies carried out during the third period, named RECENT STUDIES, that extends from 1990 to present days. We show how the blind person with good echolocation ability becomes an excellent experimental model to study behavioral and neurophysiological aspects involved in implicit learning. The article illustrates the paradigm shifts that occurred in recent scientific history through the study of this particular human ability that, within the mentioned recent theoretical context, has acquired a renewed interest.