Dyslexia of visual-spatial type - caused by disorders of perception of visual memory and spatial perception.

Dyslexia of auditory-language type - caused by disorders of perception and auditory memory and, most of all, by disorders of development of language functions (in particular, phonemic hearing
and phonological skills).

Mixed dyslexia type - auditory-language disorders and visual-spatial disorders.

Dyslexia of integrational type - caused by disorders of integrations of visual-spatial, auditory-language, tactile-kinaesthetic and motor functions (Bogdanowicz 2004).

Specific difficulties in learning are demonstrated in a few forms:

Dyslexia - specific difficulties in reading, most often, in connection with difficulties in mastering correct spelling.

Dysorthographia - difficulties in mastering correct spelling (including orthography). Specific difficulties in expressing oneself with writing (writing texts).

Dyscalculia - difficulties in learning arithmetic.

Dyspraxia - difficulties in making correct motions.

Dysgraphia - difficulties in mastering the correct graphical level of hand-writing.

The aforementioned difficulties can occur at the same time or separately. 

• difficult behaviour,
• weak motivation for work and concentration difficulties,
• irregularities in emotional and/or social development,
• misunderstanding child’s problems by their environment and family, environment’s and family’s reluctance, negative evaluation directed to parents, blaming parents for being not resourceful; sense of parental helplessness.
• motor clumsiness, difficulties in planning motion,
• difficulties in establishing contact,
• lack of cognitive curiosity, passiveness, low interest in the environment,
• hyperactivity, weak concentration
• risk of neuro-developmental disorders connected with smoking cigarettes, drinking alcohol and drug abuse by a mother during pregnancy period.
• prematurity (with delay of speech and language development, concentration disorders, hyperactivity and behaviour problems as well as with general developmental delay or eyesight deficit)
• children from a group of perinatal risk (abnormal pregnancy course and complicated delivery, low birth mass, untypical neurological symptoms).

The psycho-motor development of children with specific difficulties in learning to read and write usually has an untypical course since it is disharmonious. Children in the neonate and post-neonate period manifest delay in speech and motor development. They utter their first words, simple and complex sentences later than their peers. They crawl poorly or not at all. They start to walk, run at late stage, they have difficulties in keeping balance. Sometimes it happens that they have lowered muscle tension. They have poor manual skills, not resourceful in self-maintenance.

1. Low motor skills of the entire body: a child has difficulties in throwing and catching a ball, learning to ride a two-wheeled bike, roller-skates, ice skates or ski, poorly runs, jumps and unwillingly participates in motor plays and PE classes.
2. Lowered motor skills of the hands: incomplete mastering self-maintenance skills connected with getting dresses (fastening buttons, tying shoelaces), washing and eating (using knife and fork), difficulties in throwing at the aim and catching.
3. Continuing two-handedness.
4. Delay in orientation in the body structure and space: a child has difficulties in indicating their body parts and defining them with right/left terms (e.g. right and left hand, leg, ear); cannot define the direction to the left and to the right from themselves (e.g. road to the right, door to the left).
5. Difficulties in correct use of adpositional phrases, expressing spatial relations: over/under, behind/in front of, inside/outside.
6. Difficulties in orientation in time, e.g. in definition of season of the year or day, specific day, hour in the clock.
7. Difficulties in coordination of hand and eye functions: draws and written in an ugly manner and with reluctance, has difficulties with drawing a rhombus, coping complex geometrical figures, drawing patterns, do not keep their writing within ruling, folds “dog ears”, hold a pencil or pen too tight, their hand gets tired too quickly.
8. Difficulties in memorising a poem, song, multiplication table, more than one instruction at the same time, difficulties in memorising names, mistaking similar names, difficulties in memorising material ordered in series and sequences, such as names of the days of the week and months, seasons of the year, alphabet letters, subsequent meals and series of numbers.
9. Speech defects, incorrect pronunciation of complex words (changing positions of sounds and syllables, sound assimilation, e.g. tape and tate), using incorrect phrases in the grammatical aspect.
10. Difficulties connected with delayed development of visual perception and visual memory, difficulties in differentiating elements from the whole as well as their synthetisation into a whole, for example, during building constructions from lego blocks, solving mosaic according to the pattern; difficulties in finding different details in two pictures. Difficulty in mastering correct spelling: difficulty in memorising the shape of less common letters, with complex structure (f, h, ł, g); mistaking similar letters in terms of shape, for example l/t/ł/ or m/n, mistaking identical letters, but differently positioned in space: p/b/d/g, making mistakes during rewriting texts.
11. Difficulties in differentiating similar sounds (e.g. z/s, b/p, k/g, that is, disorders of phoneme hearing); difficulties in separating syllables and sounds from words, their synthetisation (disorders of sound and syllabic analysis and synthesis) as well as manipulation with word phonological structure (e.g. find words hidden in the name “sunflower”, think of a rhyme to word “kitten”. guess what I am thinking of: “Post ...ox”). Difficulties in mastering correct spelling connected with delayed development of auditory perception of speech sounds, auditory memory and speech: mistaking letters corresponding to phonetically similar sounds (e.g. sounds z/s, w/f, d/t, k/g), difficulties with writing down palatalization, mistaking sounds i/j, nasal sounds ą/om, ę/en, notorious skipping, adding, misplacing, doubling letters and syllables, writing nonsensical words, highly intensified difficulties in writing from hearing (dictations).
12. Difficulties in learning to read, for example, a child reads really slowly, most often sounds and not always performs correct, secondary synthesis, incorrectly pronounces words, does not understand the read text.
13. First writing attempts - often writes letters and digits in a mirror reflection as well as copies words, writing them down from right to left, does not remember letters.

Genetic concept - (20%-30%), the cause of disorders and base of difficulties in reading and writing are genes transferred from one generation to another, i.e. dyslexia heredity,

Concept of delayed maturation of the nervous system - it is believed that dyslexic disorders are connected with the slowed down maturation of the central nervous system caused by such factors as genes, hormones,

Organic concept goes that the cause of dyslexia are micro damages of brain regions which have a particular participation in the reading and writing process. It is connected with harmful chemical, physical and biological factors impacting the CNS in the perinatal period,

Hormonal concept - sees the cause of dyslexia in insufficient development of some regions of cerebral cortex and incorrect model of brain development, i.e. blocking the development of the left hemisphere, i.e. one that is particularly connected with speech; testosterone overproduction can be a harmful factor.

Psychogenic concept - sees the cause in emotional disorders arising from anxiety, stress and mental trauma. In the most cases, it is a mutual linkage of different factors which impact on the development of cognitive processes (perception, language), motor activity and integration of these functions. There are also cases of dyslexia with minor symptoms when it is the result of heredity or disorders in the narrow scope.

Examples of famous dyslexics: Albert Einstein, Isaac Newton, Leonardo da Vinci, Charles Darwin, Pablo Picasso, Henry Ford, Vincent van Gogh, Nelson Rockefeller, Winston Churchill, John F. Kennedy, Alexander Bell, Hans Christian Andersen, Ernest Hemingway, Charles Dickens, Walt Disney, Steven Spielberg, Mozart, Ludwig van Beethoven, Robbie Williams, Tom Cruise, Thomas Edison, Marilyn Monroe, Fred Astaire, Salma Hayek, Goldie Hawn, Robin Williams, George Washington, Whoopi Goldberg