الفهرس 
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Abstract
A categorization consists of defining the properties that are shared by several objects. The combinations of these properties are used to construct classes of objects that are considered similar. In consequence, categorization processes are fundamental in structuring not only perceptual but also cognitive skills.
In the current study, Sound categorization test was developed and applied for cochlear implant children to evaluate the recognition and identification of nonlinguistic sounds compared to their peers with normal hearing. Two groups of participants (NH children and children with CIs) were examined for Sound categorization test using free sorting task procedure (FST) featuring everyday sounds. A set of 18 natural stimuli were studied. They were chosen to cover a broad range of everyday sounds that corresponded to four main a priori categories: nonlinguistic human vocalizations, animal vocalizations, environmental sounds& musical instruments. Children were asked to name/identify the sounds in an open-set identification task, then group the sounds that go well together creating different number of categories.
Results showed that the Cochlear Implant users were different from normal hearing listeners regarding the perception of individual sounds. Normal hearing children could identify sounds better than the CI children. Sound identification scores increased with increasing chronological age of both groups. By examining performances for the different a priori sound categories, the results revealed a substantial difference for identification of the human non-linguistic and animal vocalizations versus other types of sounds. Moreover, the cochlear implant children have reduced relative ability toward identification of superordinate category of non-linguistic human vocalizations compared to age and gender matched normal hearing children.
Considering the process of categorizing sounds, NH children tend to perform many categories of similar sounds compared to CI children. CI children performance was based on the perception of semantic information associated to the sound producing event. This would suggest that “top-down “processes involved in categorization were well developed and possibly driving the strategies used by CI children.
Above findings support that everyday sounds categorization would be a crucial aspect of the perception of the surrounding world. Categorical perception is recommended to be used as a useful tool in rehabilitating CI, especially in learning how to differentiate different kinds of sounds and for dealing with real world environments when many different kinds of sounds could be going on at the same time.