ory ▁Group ▁for ▁President ▁Ford , ▁cha ired ▁the ▁Fif teenth ▁An ni versary ▁Head ▁Start ▁Committee ▁which ▁President ▁Carter ▁task ed ▁to ▁plan ▁the ▁future ▁course ▁of ▁the ▁Head ▁Start ▁program , ▁and ▁helped ▁to ▁construct ▁the ▁Family ▁and ▁Medical ▁Le ave ▁Act ▁. ▁ ▁In ▁ 1 9 7 8 , ▁Z ig ler ▁founded ▁the ▁Bush ▁Center ▁for ▁Child ▁Development ▁and ▁Social ▁Policy ▁at ▁Y ale ▁University ▁with ▁fund ing ▁from ▁the ▁Bush ▁Foundation ▁of ▁Minnesota . ▁The ▁focus ▁of ▁the ▁center ▁is ▁to ▁use ▁the ▁find ings ▁of ▁empir ical ▁research ▁on ▁child ▁development ▁to ▁inform ▁public ▁policy ▁efforts ▁to ▁improve ▁children ' s ▁lives . ▁The ▁center ▁was ▁renamed ▁as ▁the ▁Edward ▁Z ig ler ▁Center ▁for ▁Child ▁Development ▁and ▁Social ▁Policy ▁in ▁ 2 0 0 5 . ▁ ▁Z ig ler ' s ▁research ▁on ▁intellectual ▁dis abilities ▁was ▁among ▁the ▁first ▁efforts ▁to ▁differenti ate ▁children ▁based ▁on ▁the ▁causes ▁of ▁their ▁intellectual ▁dis abilities . ▁ ▁His ▁" two - group " ▁approach ▁to ▁what ▁was ▁then ▁referred ▁to ▁as ▁" ment al ▁ret ard ation ," ▁differenti ated ▁those ▁children ▁whose ▁dis abilities ▁were ▁believed ▁to ▁be ▁caused ▁by ▁famil ial / environment al ▁factors , ▁from ▁children ▁with ▁known ▁bi ological ▁cases , ▁such ▁as ▁gen etic ▁synd rom es . ▁This ▁work , ▁which ▁was ▁influenced ▁by ▁the ▁development al ▁the or ist ▁Hein z ▁Werner , ▁lay ▁the ▁foundation ▁for ▁more ▁ ▁a ▁meaning ful ▁tax onomy ▁of ▁intellectual ▁dis