Purpose: Hearing impaired children are heavily dependent on their sense of vision to develop efficient communication skills; any contrast sensitivity defect can negatively impact their lives because they are not able to use auditory stimuli to recognize probable dangers in the world around them. The purpose of this study was to determine the contrast sensitivity abnormalities in deaf individuals. Methods: In this cross‑ sectional study, contrast sensitivity of 15‑ to 20‑ year‑ old high‑ school boys with hearing disability from Tehran, Iran were evaluated. Sixty‑ four eyes were tested for contrast sensitivity and refractive error. All subjects had an intelligence quotient (IQ) >70. We investigated their contrast sensitivity with Vector vision CVS‑ 1000 in 4 different spatial frequencies. Results: Profound hearing loss was noted in 50% of the subjects. The frequency of contrast sensitivity abnormalities in 4 different spatial frequencies varied between 51. 6% and 65. 6%. The largest abnormalities were recorded at 18 cycles per degree. Only 12. 5% of deaf students had corrected distance visual acuity (CDVA) greater than zero (in LogMAR). The abnormalities in contrast sensitivity showed no correlation with the type or severity of hearing loss. Conclusion: Hearing impaired boys are at a greater risk for contrast sensitivity abnormalities than boys with normal hearing. The larger frequency of contrast sensitivity abnormalities in high spatial frequencies than in other frequencies may demonstrate greater defects in the central visual system compared with the periphery in individuals with hearing loss.

Deafness is a heterogeneous condition with far-reaching effects on social, emotional, and cognitive development. Many regard themselves as members of a cultural minority who use sign language. They should not continue to be neglected in research on depression. The purpose of this article is to investigate depression among the deaf people based on researches results. We identified relevant studies by searching the computerized databases Science Direct, PsycINFO and Medline. Additional relevant studies were identified through the reference sections of studies found during the initial search. In this article we retrieved 11 articles, 8 of them indicated a higher degree of depression amongst deaf people in comparison with hearing ones. The remaining 3 articles showed no difference between two groups. In addition anxiety disorders and insomnia were the highest degrees after depression in deaf people. Mild levels of depressive symptoms are more prevalent in the deaf than in hearing students but more severe depression is not. Although there is no evidence in the literature to suggest that Deaf adults do not experience depressive symptoms, the typical methods of assessing depressive symptoms among the population are inadequate and unreliable.

The ability to understand that other people have mental states such as thoughts, desires and beliefs that may be different from one's own is termed as "theory of mind". In this article, firstly, we discuss about theoretical basics of theory of mind, and then we review published researches about theory of mind development in deaf children. We answer two questions; do deaf children delay in development of theory of mind? And, Do deafness of parents impact theory of mind development of deaf children? Some theorisians believe that development of theory of mind related to language; in other side are theorisians who believe theory of mind development is related with executive functions. Some researches show delay in theory of mind development in deaf children. Few researches show no delay in theory of mind development in deaf children. Studies about the impact of parental deafness on development of their deaf children theory of mind indicated no delay. These children are similar with hearing children in theory of mind development.