Question

1. (A) With respect to perception, describe the brain structures and functions, as well as cognitive processes if applicable, underlying color identification, object identification, and movement; (B) Describe the flow of visual information from the eye to the primary visual cortex. Then describe the neural systems for perceiving shape, identifying what an object is, and identifying where an object is located in space and how it can be utilized.

2. Describe the three major structures and functions of the outer, middle, and inner ear.

3. What are the types of touch receptors located under the skin's surface? Describe how touch is represented in the brain.

4. Compare and contrast the two chemical senses of smell and taste. Include (a) a discussion of the sensory receptors for smell and taste and (b) a discussion of the pathways by which smell and taste sensations are transmitted.

5. You are drawing an outdoor scene, including trees, flowers, shrubbery, and buildings near and far from your position at your easel. Describe how you would use at least four monocular cues to indicate depth and dimension in your drawing.

Answer 1

1.A. Colour identification refers to the perception of colour based on the wavelength of visible light that enters the visual sensory receptor or the retina of the two eyes. The associate areas of V4 located in the inferior gyrus of the occipital lobe is associated with the perception and recognition of colour constancy for different wavelengths of light. Moroever, V4 is involved in the automatic color constancy operations . The final stage in colour perception is based in the inferior temporal and frontal cortices and it involves processeing information for colored objects based on memory, judgment and past learning.

The perception of movement and space is interpreted and stored by the brain’s Visual Center or the Occipital lobe and parts of the temporal lobe in the cerebral cortex. In particular, motion pathway extends into the parietal cortex which is specialized for registering information about the locations of objects and their movements and it sends information about the recognition of shape and size of these visual objects.

In identifying new objects, the memory processes the new information and compares templates, which are mental representations used to compare previously viewed shapes in the retinal image. Identification of objects is a task which is largely carried out by the inferior temporal cortex.

1.B. The visual perception takes place in the sensory-motor visual pathway that Carries information from the visual sensory receptors or the the retina in the eyes to the occipital cortex in the brian. The light waves which enter the eye get refracted through the lens of the eyes and stimulate the rods and cones in the retina which help in perception of darkness and colours of objects in light. The information from the retina then passes into the optic nerve which connects the two eyes to the occipital cortex. The fibers of an optic nerve travel through the optic chiasm where there is a crossing over of the information such that the sensory input from the left eye reaches the right hemisphere and the input form the right eye is transferred to the left hemisphere. After the optic chiasma, to information is relayed to the lateral geniculate body of the thalamus, and from here, they travel to the optic radiations terminating in the occipital lobe.

This Neural pathway is involved in a multiple array of visual perception ranging from, perception of colours to recognising movement, size constancy, as well as perceiving and recognising the shape of objects in the changing visual plane.

In this regard it isn’t seen that Changes in the observer- object distance can produce variation such in the size of the retinal image. However, the presence of depth cues and movement cues in the environment are used as secondary sources for interpreting the actual size of the object and this results in size and shape constancy and the recognition of the particular object with a familiar shape or size. Interestingly, it has been reported that chnages in the movement of the observer leads to better size and shape constancy than the chnages in the retinal image that result from the shifting movement of the object.