Table 1.

Types of plasticity and influencing factors.

Type	Function
(1) Strengthening of cognitive functions	Skill learning (e.g., [145])
(2) Hemispherectomy	Removal of one hemisphere to treat a variety of seizure disorders, leading to a takeover of functions that were initially performed by or in combination with the removed hemisphere (e.g., [146])
(3) Sensory substitution	Compensation of sensory loss by another sense or external device (e.g., [147]); for a review addressing differences within hearing restoration by cochlear implantation, see [97]
(4) Early deprivation	Early loss due to a genetic or medical condition leading to compensation and broad takeover by other senses, although functional topography appears inert as dual streams (dorsal and ventral) remain intact; reorganization mainly occurs through bottom-up processing (e.g., [148, 2])
(5) Late deprivation	Rather supportive in nature; compensation for the loss is restricted due to initial pruning and functional reorganization; rather through top-down processes (e.g., [148, 2])
(6) Site of plastic changes	Cross-modal, intracortical, or even within the sensory organ (e.g., the retina [144])
Influencing factors
(1) Sensitive/critical periods
(2) Other senses and their critical periods [149]
(3) Age of onset of deprivation
(4) Duration of deprivation
(5) Degree of loss [142]
(6) Cause of sensory deprivation
(7) Working memory, intelligence quotient, gender (…) (e.g., see also the Ease of Language Understanding (ELU) model [150])