Dyslexia is a general term used to describe an unexpected, severe, and persistent difficulty in learning to read. By far the most common learning disability, accounting for an estimated 80% of all learning disabilities ( Shaywitz, 2003), and at least 5% of the population. It does not result from low intelligence or mental retardation, visual or hearing defects, poor teaching, or lack of educational opportunity. With early intervention and treatment, most children with dyslexia can attain adults careers comparable to people with similar IQs.

Most cases of Dyslexia are not recognized until about the 3rd grade.

Common Forms of Dyslexia

Dyslexia can take many different forms and vary in severity. However, most cases can be grouped into the following three categories:

Visual Dyslexia
Difficulty with processing what is read.

Auditory Dyslexia
Difficulty processing what is heard

Mixed Dyslexia
Difficulties with visual and auditory processing

Symptom Profile

Although the symptoms of dyslexia can very considerably among individuals, common symptoms include difficulties involving any or all of the following:

  1. Learning and remembering printed words
  2. Figure-ground perception
  3. Discriminating between sounds (e.g., mind and mine)
  4. Errors in letter-sound association
  5. Short-term memory
  6. Letter confusions
  7. Letter reversals
  8. Skipping words
  9. Recognition of words on sight setting "stuck" on a word or sentence (repeating)
  10. Insertions and substitutions of words and letters
  11. Difficulty blending sounds and syllables
  12. Comprehension
  13. Excessive effort required to read
  14. Difficulty maintaining sequential order of written material
  15. Difficulty with oral expression
  16. Persistent spelling errors
  17. Handwriting
  18. Arithmetic and mathematical calculation


Dysgraphia is a specific learning disability involving impairment in the ability to process and report information in written form. Learning to write is a complex task, involving the complex integration of several processes, including visual perception, sensory-motor integration, motor planning, memory, and spatial processing. Impairments in any or all of these areas can result in significant difficulties in the acquisition of writing skills. People with dysgraphia have severe difficulty getting the hands and eye to work together smoothly, resulting in handwriting that is sloppy, disorganized, and often completely illegible. Although the specific nature of difficulty can vary considerably from person to person, symptoms commonly include:

  • Slow acquisition of writing skills
  • Difficulty remembering the shapes of letters and numbers
  • Problems with letter/number formation
  • Mirror writing
  • Reversal of letters and numbers
  • Problems with page layouts
  • Uneven spacing
  • Omission of letters/numbers
  • Repetition of letters/numbers
  • Disorganized, sloppy papers
  • Many cross-outs and erasures
  • Errors in capitalization
  • Frequent errors in punctuation
  • Spelling errors
  • Excessive time and energy required to complete writing assignments
  • Errors in word usage and grammar


The diagnosis of dysgraphia (also known as a "disorder of Written Expression") is made only when writing skills are substantially below the expected based on chronological age, intelligence, and age appropriate education. In addition, the difficulties significantly interfere with academic achievement or activities of daily living that require expressive writing skills (1). Many people with dysgraphia also have other areas of difficulty. Dysgraphia is frequently associated with dyslexia, attention deficit and memory disorders, and mathematical learning disability (dyscalculia).

  1. Adapted from: The Diagnostic and Statistical Manual of Mental Disorders, 4th edition. American Psychiatric Association, 1994.


Dyscalculia, or "math disorder", is a learning disability involving server difficulties in learning to perform basic arithmetic calculations. Although the specific nature of difficulty can vary considerably areas : (1) impairments in linguistic processing skills involving mathematical terms and concepts; (2) impairments in perceptual skills in recognizing numerical symbols; (3) attention and memory problems that interfere with copying correctly and following procedures; and (4) decoding written problems.

The underlying causes of dyscalculia are not well understood. However, most of the difficulties associated with dyscalculia suggest that right hemisphere parietal lobe dysfunctions are likely play a significant role. Some researchers (Rourke, 1978; Temple, 1992) hold that there may be several different forms of dyscalculia, all having a different symptom profile and cause. Common areas of difficulty include:

Common Areas of Difficulty

  • Difficulty understanding basic number concepts
  • Difficulty understanding numerical relationship
  • Errors involving basic number concepts
  • Error involving reading and writing numbers
  • Problems counting
  • Problems learning calculations
  • Problems learning multiplication tables
  • Errors involving enumeration
  • Reversal of written numbers
  • Excessive time and energy required to carry out arithmetic problems
  • Difficulty with words problems
  • Problems with aligning columns
  • Difficulty with measurement
  • Avoidance of anything having to do with numbers
  • Emotional distress related to arithmetic
  • Poor frustration tolerance with tasks involving numbers
  • Perseveration (e.g., if the first question on a arithmetic assignment is addition, the child may continue to do addition even when the other problems are subtraction).


Dyscalculia is thought to affect around 6% of the population, although some researchers suggest the rates may be higher. It is frequently associated with reading, handwriting and other learning disabilities, although it sometimes occurs alone. The diagnosis of dyscalculia is made only when mathematical ability is substantially below the expected based on chronological age, intelligence, and age appropriate education. In addition, the difficulties significantly interfere with academic achievement of activities of daily living that require mathematical ability.

Resource: Mr. Ernie Jones, Problems of Childhood 2006, Department of Psychology Las Positas College, CA.