TABLE 5.

Main functions and characteristics of competence, acquisition and performance levels as related to individual differences in learning skills and comorbidity of learning disorders.

	Function(s)	Characteristics	Specificity/overlap
Competence	Ability to activate a specific set of representations and processes	- Domain-dependent - Task-independent - Sensitive to practice	Dissociation of deficit may be present to the extent in which different processes rest upon different sets of representations and algorithms
Acquisition	- learning specific rules and/or regularities (algorithms and core competence) - learning direct memory traces (instances) which are automatically retrieved and coercively activated in the presence of appropriate stimulation - Upon practice, the child gets accustomed to the typical task format, characteristic of a given behavior (e.g., reading a text in a left to right manner).	- Domain-dependent - item specific - Domain-independent It follows a general law a practice, characterized by a slow pacing of learning (long periods for over-learning and automatic responding) - Partially domain-dependent	Consolidation of instances may dissociate from learning of algorithms. Deficits in developing automaticity may lead to learning disorders across different domains (comorbidity)
Performance	Actual performance depends on the characteristics of the task which may call into action different processes depending upon the specific competence involved or/and the characteristics of the task itself (e.g., a speed task).	- Task-dependent - Partially domain-dependent - Sensitive to practice	It may lead to both associations and dissociations of learning skills (and disabilities) depending on the degree of overlap of: task-specific processes and their interaction with specific “competence” requirements