Evidence for visual imagery deficits in persons with mental retardation

Performance on four mental imagery tasks by two groups of adolescents with mental retardation with different etiologies (sociocultural, organic) were compared to that of children without mental retardation who were of comparable or lower MAs. Findings reveal an important deficit in imagery abilities in both retarded groups; their performance was poorer compared to the children without mental retardation matched on MA. Subjects with mental retardation due to sociocultural retardation scored higher on some tasks than did those whose mental retardation was due to organic causes. This finding underscores the need to consider etiology. This marked deficit in imagery ability in persons with mental retardation may be the source of other difficulties they encounter in cognitive activities that involve this representational format.