With respect to any investment made by an association in a loan, in the event the ownership of the security for the loan or any part thereof becomes vested in a person other than the parties originally executing the security instruments, and provided there is not an agreement in writing to the contrary, the association may, without notice to the original parties, deal with the successors in interest with reference to the security and the debt thereby secured in the same manner as if the property were owned by the original parties, and may forbear to sue or may extend time for payment of or otherwise modify the terms of the debt secured thereby, without discharging or in any way affecting the original liability of the parties thereunder or under the debt thereby secured.