In his search for the elusive memory trace karl lashley finally concluded that memory was the brain.

Karl Lashley was searching for the engram or the memory trace, a theoretical vehicle by which our memories would be physically stored in the brain, from 1929 to 1950. He believed that memory was stored in the particular area of the brain but instead through his experiments concluded that the memories were scatted, distributed across the brain. Today it is agreed that memories are distributed across the brain but the actual method of their storage is still debated and unknown.  

explanation:

allergens: overstimulate the nerve system

neurotics: attack nerve cells

mutagens: damage or otherwise alter dna sequence

generators: cause defects during growth and development  

carcinogens: cause unchecked cell growth

i hope you get the idea according to me these are the effects that happened.

what he said above me         look up that's the answer