ABSTRACT
Se realizó una investigación analítica y prospectiva, de casos y controles, de los niños con glaucoma o estrabismo, o ambos, atendidos en la consulta de Oftalmología del Hospital Infantil Sur de Santiago de Cuba, de enero a junio del 2011, a fin de evaluar la percepción visual del movimiento coherente en ellos. El grupo de casos incluyó 72 pacientes escogidos de forma aleatoria, y el de controles, igual cantidad de integrantes que presentaban toda su capacidad visual. Se determinó que los niños con afecciones en la visión cometían más errores, omisiones y menos aciertos, además de ser menos rápidos en la solución de los ensayos orientados, pues tuvieron mayor tiempo de reacción para ejecutarlos.
A prospective analytic case-control study was carried out in children with glaucoma or strabismus or both, treated at the Department of Ophthalmology of the Southern Children Hospital in Santiago de Cuba, from January to June 2011, with the purpose of assessing the visual perception of coherent motion in them. The case group included 72 randomly selected patients, and control group with the same number of members who had all their vision. It was determined that children with visual disorders made more errors, omissions and fewer hits, besides being less rapid in solving oriented tests, as they had longer reaction time to do them.
ABSTRACT
Se aplicó una tarea de detección visual del movimiento coherente, confeccionada en el Centro de Neurociencias y Procesamiento de Imágenes y Señales de la Universidad de Oriente, en Santiago de Cuba, mediante la cual se determinó que los escolares disléxicos estudiados podían detectar el movimiento visual, pero cometían muchos errores y omisiones, indicativos de un ligero debilitamiento del proceso de detección visual. También se observaron deficiencias perceptivas en ellos, relacionadas con el incremento de la densidad de los puntos que se movían en los paneles y su disminución porcentual, así como también con el aumento del tiempo de respuesta, reveladores de una reducción de la sensibilidad a la percepción visual del movimiento en estos alumnos con dislexia del desarrollo.
A task of visual detection of the coherent movement, made in the Neurosciences and Processing of Images and Signs Center from Oriente University was applied in Santiago de Cuba, by means of which it was determined that the dyslexic students studied, could detect the visual movement, but they made many mistakes and omissions, indicative of a slight weakening of the visual detection process. Perceptive deficiencies were also observed in them, related with the increment of the density of the points which moved in the panels and their percentage decrease, as well as with the increase of the response time, showing of a reduction of the sensibility to the visual perception of movement in these students with development dyslexia.
ABSTRACT
Histology and morphometry of the eye in the freshwater Paracheirodon axelrodi (Characiformes: Characidae). The visual system of Teleost fishes has a wide range of adaptations. The eye has suffered modifications, mainly towards better sensitivity and visual resolution according to specific environmental conditions. In that way, this organ is so important for survival. In spite of being the most commercialized Orinoquía species, and one of the most important ornamental fish worldwide, there are almost no studies on the communication systems of P. axelrodi (including vision). We studied the eye in ten individuals of P. axelrodi, with a mean total length of 2.7 cm (SD= 0.2, n= 20). We measured eye relative size (TRO) after sacrifice. Heads were processed for hematoxylin-eosin, and 8 μm thick sections were obtained. Images were digitalized for histological identification and morphometrics. The relation between TRO and body length was 9.8% (SD= 1.1, n= 20); lens was spherical with a relative size of 64.3% (SD= 4.9, n= 20). Rete mirabilis choroid was composed mainly by capillaries, while sclera was composed of cartilaginous tissue. Retina with eight layers and two membranes. An areae centrales was observed in the posterior retina. Iris covered by a simple cubic epithelium. Cornea of endothelial tissue with two membranes. Pupil almost circular, with a naso-caudal elongation. Measures of retina thickness were as follows: lateral retina 144.5 μm (SD= 5.4, n= 20), temporal retina 210.4 μm (SD= 14.8, n= 20). Lens measurements were: dorso- ventral 759.6 μm (SD= 31.7, n= 20), antero-posterior 763.4 μm (SD= 30.7, n= 20). Cornea thickness was 27.6 μm (SD= 4.3, n= 20); iris thickness was 18.9 μm (SD= 1.9, n= 20); rete mirabilis choroid 22.2 μm (SD= 3.2, n= 20) and sclera: 15.9 μm (SD= 1.2, n= 20). This species has a typical Teleost eye conformation. The retina was thicker in the posterior area, probably related to the presence of neuron groups. This modification allows for a better sharpness and visual resolution. The TRO, areae centrales in the retina, and thin cornea, suggests the need of a well developed visual system resulting from a predatory diet. Rev. Biol. Trop. 57 (4): 1107-1118. Epub 2009 December 01.
El pez dulceacuícola P. axelrodi es de gran importancia comercial en la Orinoquía Colombiana y a nivel mundial, pero carece de estudios acerca de su visión. Se utilizaron diez individuos, con longitud total promedio de 2.7 cm (SD= 0.2, n= 20). Se realizaron cortes a 8 μm y se tiρeron con H-E. El tamaρo relativo del ojo es 9.8% (SD= 1.1, n= 20); el cristalino tiene un tamaρo relativo de 64.3% (SD= 4.9, n=20). Una esclerótica con tejido cartilaginoso. La retina está constituida por ocho capas y dos membranas, hay areae centrales en la zona posterior, por lo tanto tiene mayor espesor que la zona lateral. El espesor promedio de las estructuras es: retina lateral: 144.5 μm (SD= 5.4, n= 20), retina temporal: 210.4 μm (SD= 14.8, n= 20); cristalino (esfιrico): dorso-ventral 759.6 μm (SD= 31.7, n= 20) y antero- posterior 763.4 μm (SD= 30.7, n= 20) y cσrnea: 27.6 μm (SD= 4.3, n= 20). El tamaρo relativo del ojo, relacionado con la presencia de areae centrales y una córnea delgada, muestra las necesidades visuales del neón cardenal (cazador) para adaptarse al hábitat, lo que hace necesario tener un sistema visual desarrollado que le permita tener mejor sensibilidad y resolución visual.