Ch 4Sensory, Attentional and Perceptual Processes — Class 11 Psychology, concept-first.

Some of the receptors that gather information for us are easy to notice, like the eyes or the ears; others sit deep inside the body and can only be studied with the help of electrical or mechanical in…

The world we live in is packed with an enormous variety of objects, people, and events, differing in size, shape, and colour -- a quick look around any room reveals furniture, books, pictures, and cou…

The external environment surrounding us is full of a wide variety of stimuli. Some can only be seen (a building), some can only be heard (a piece of music), some can only be smelled (the fragrance of…

Our sense organs give us first-hand information about the world outside us as well as about our own internal body.

Our sense organs, however capable, all function within definite limits. The eyes cannot register light that is too dim or too intensely bright to see; in the same way, the ears cannot register sounds…

A large number of stimuli reach our sense organs at the very same time, yet we clearly do not notice all of them simultaneously -- only a selected few actually register in our awareness.

Selective attention is mainly concerned with the selection of a limited number of stimuli or objects from among a much larger number of competing stimuli.

While selective attention is mainly concerned with choosing among stimuli, sustained attention is concerned instead with concentration -- our ability to maintain attention on a particular object or ev…

The stimulation of our sense organs gives us an elementary experience -- a flash of light, a sound, a smell -- but this basic experience, called sensation, does not by itself tell us anything about th…

How exactly do we identify an object? Do we recognise a dog, for instance, because we have first recognised its individual features -- its furry coat, its four legs, its eyes, its ears -- and then bui…

Human beings are not simply mechanical, passive recipients of whatever stimuli happen to reach them from the external world.

A perceiver's own needs and desires exert a strong influence on what that person perceives. People generally want to fulfil their various needs and desires, and one way this happens is by perceiving a…

Our expectations about what we are likely to perceive in a given situation also shape our actual perception.

Cognitive style refers to a person's consistent, characteristic way of dealing with their environment, and it significantly affects the way that person goes on to perceive that environment.

The different experiences and learning opportunities available to people living in different cultural settings also shape their perception in genuine, documented ways.

Our visual field, considered purely as raw sensory input, is really just a collection of separate elements -- points, lines, and patches of colour.

When we look at any visual surface, certain aspects of that surface clearly stand out as separate entities, while others do not.

Objects that are close together in space or in time tend to be perceived as belonging together, as forming a single group.

Objects that are similar to one another, and that share similar characteristics, are perceived as belonging to a single group.

This principle states that we tend to perceive objects as belonging together if they appear to form a continuous pattern.

According to this principle, smaller enclosed areas within a display tend to be perceived as the figure, seen against a comparatively larger surrounding area that becomes the background.

This principle suggests that symmetrical areas within a display tend to be perceived as the figure, set against comparatively asymmetrical surrounding areas that become the background.

According to this principle, an area that is surrounded by other areas tends to be perceived as the figure.

We tend to fill in small gaps in the stimulation we receive and perceive objects as complete wholes, rather than perceiving them as their separate, disconnected parts.

The visual field or surface within which things exist, move, or can be placed is called space. The space we live in is organised in three dimensions, and we perceive not just the spatial attributes of…

Monocular cues to depth perception are effective when objects are viewed with only one eye. These cues are often used deliberately by artists to create a sense of depth within two-dimensional painting…

Some important cues to depth perception in three-dimensional space are provided jointly by both eyes; three of these have been found to be particularly interesting.

The sensory information we receive from our environment is constantly changing as we move around within it.

The size of an object's image on our retina changes as the distance of that object from the eye changes -- the farther away it is, the smaller the resulting retinal image.

In our everyday perception, the shapes of familiar objects remain unchanged for us despite changes in the pattern of the retinal image caused by differences in the object's orientation relative to us.…

Visual objects appear constant to us not only in their shape and size, but also in their degree of whiteness, greyness, or blackness, even though the actual amount of physical light energy reflected f…

Our perceptions are not always veridical -- that is, they do not always match physical reality with complete accuracy.

One of the best-known geometrical illusions is the Muller-Lyer illusion, in which two horizontal line segments of exactly equal length are shown, labelled A and B.

This illusion is experienced when a series of motionless pictures is projected one after another at an appropriate rate, referred to as the "phi-phenomenon".

Several psychologists have studied the processes of perception as they occur across different socio-cultural settings.