Products that contain bismuth can temporarily turn your tongue black, according to Atlas of Adult Physical Diagnosis. Other Causes If you have a black tongue, then you could have a fungus called Aspergillus niger growing on the surface of your tongue. If you have too much bacteria growing in your mouth, it could cause your tongue to appear black and hairy, according to the Mayo Clinic.
In addition, a child is said to have a cognitive delay and/or a learning disability when they are performing at least two grade levels below their peers. For example, a third grade class is learning their multiplication tables, but a student with a cognitive delay would be performing math on a first grade level.
A language delay is a communication disorder. A child is said to have a language delay if he or she does not meet the language developmental milestones for his or her age.Language may be developing, but it is at a slower rate than the norm for the child's age.A language delay can involve a hearing, speech, or language impairment, or a combination of two impairments or all three. Language and speech disorders are common.According to the University of Michigan Health System, they affect up to 10 percent of preschool-age children (University of Michigan Health System) .ome common causes include: 1  Hearing impairment: It is common for children who have a hearing impairment to also have a language impairment. 2  Autism: Although not all children with autism have language delays, autism frequently affects communication. 3  Psychosocial factors: Several psychosocial issues can cause language delays. 4  Intellectual ...