HSD-11βs are expressed in the central nervous system of aged individuals. It is essential in Hypothalamo-Pituitary-Adrenal Axis function. HSD-11βs also partakes involvement in the decline of conscious intellectual activity due to aging. The enzyme also contributes to central effects are also during the development stages. For instance, the HSD-11βs Type 2shows frequently in fetal tissues such as a newborn's brain and placenta. If there is an absence or decline in HSD-11βs Type 2 in the fetus tissues, there are negative developmental consequences such as anxiety.