Lichenification occurs in which layer of skin:

Lichenification is seen in Stratum malpighii (stratum Spinosum along with stratum basale) LICHENIFICATION- Thickening of the epidermis (and to some extent also of the dermis) in response to prolonged rubbing. It is a secondary skin hyperophy ; thick, leathery skin, giving the skin a leathery bark-like appearance. It is a common consequence of atopic dermatitis;eczema and other pruritic disorders. Associated with acanthosis( thickening of stratum spinosum)