Auditory Hallucination or Paracusia is a form of hallucination that involves perceiving sounds without auditory stimulus. A common is hearing one or more talking voices which is associated with psychotic disorders such as schizophrenia or mania. Hallucination, itself, is the most common feature of perceiving the wrong stimulus or to the better word perception of the absence stimulus.Here we will discuss four definitions of hallucinations:1. Perceiving of a stimulus without the presence of any subject2. hallucination proper which are the wrong perceptions that are not the falsification of real perception, Although manifest as a new subject and happen along with and synchronously with a real perception3. hallucination is an out-of-body perception which has no accordance with a real subject In a stricter sense, hallucinations are defined as perceptions in a conscious and awake state in the absence of external stimuli which have qualities of real perception, in that they are vivid, substantial, and located in external objective space. We are going to discuss it in details here.

Background and Aim: There are evidences that indicate a relationship between auditory processing disorders and stuttering, and any disorder in the central auditory function can be at least one of the underlying causes of stuttering. Even though, using the most state of the art radiographic technologies, i.e. MRI, no definitive answer has been given in relative to this question. In this research, using Mask-ing Level Difference (MLD) and Synthetic Sentence Identification (SSI) tests, the central auditory function of stutters and normal group was evaluated.
Materials and Methods: In this study was analytic cross-sectional, fifteen male patients with stutter-ing and 15 male normal cases with the age range from 16 to 40 years (average age 26.78 year) were evaluated. SSI-ICM, SSI-CCM and MLD tests were performed. The results were compared in both groups.
Results: Although stutterers mean MLD was less than that of normal group, the different was not significant between stutters and normal group in SSI test in right ear at negative MCRs. There was a significant difference in ICM state, but in CCM state, there was no significant difference between the average score of two groups in various MCRs.
Conclusion: The findings of this research is compatible with those of similar researches about the SSI test and the pattern of results, probably indicates a partial dysfunction of brainstem in some of the stutters.

Background and Aim: Although double dichotic digit test is a useful tool for assessing the central auditory system in adults, it is more useful for evaluating younger children. The present study aimed to develop the Persian version of the single dichotic digit test and to obtain initial normative data.

Methods: The Persian version of the present test consisted of three different sets of 25 single digit pairs for testing in the free recall, directed recall to right, and directed recall to left conditions. The digits in each list were recorded dichotically on a compact disc. The sectional study was performed on 126 male students, aged between 7 and 9. The test-retest reliability was assessed in 29 subjects two to four weeks after the first test session.

Results: In seven year olds, the mean right and left ear scores increased from around 95.79% and 89.69%, respectively. In eight year olds, the mean right and left ear scores increased from around 98.59% and 96.29%, respectively. The mean right ear advantage decreased from around 6.13% in 7 year olds to around 2% in 8 year olds (p=0.001). No significant difference was found in scores between the free recall and directed recall conditions (p>0.05). The test had a high test-retest reliability (p>0.05).

Conclusion: The Persian version of the test has a high test-retest reliability for evaluating male children aged between 7 and 9 it can be used for assessing binaural integration in male children of this age group.