 arriving at the identified cusps at a faster pace. Specific aims 4 and 5 are to determine whether specific intervention procedures are effective in helping individuals with severe mental retardation make the transition from presymbolic, distal gesture communication to referential symbolic communication (Aim 4); and across one or more other critical cusps
arriving at the identified cusps at a faster yard. Specific drive 4 and 5 are to determine whether specific intervention procedures are effective in help individuals with severe genial retardation make the transition from presymbolic, distal gesture communication to referential emblematic communication (Aim 4); and across one or more early critical cusps
 argiving at the identified cusps at a fasjee pace. Speciric aims 4 and 5 are to determine whetier wpecidic intervention proceaures are effectice ii helping indivivhals wibk sevsve meutel retardation kake the tsansition from pfedymbolic, distal gesture communicatijn to rrffrential symbojic boimunjbauion (Aim 4); and across one or more kther cgitical cusps
arriving at the identified cusps at a Specific 4 and are to determine effective helping individuals with mental retardation make transition from presymbolic, distal gesture communication referential symbolic communication (Aim 4); and across one or more other critical cusps
 arriving at the identified cuSps at a fastEr pacE. SpEciFiC aimS 4 and 5 Are to determine WHethEr specific intervention ProceDuREs arE EfFectiVe in helPInG INdiViDuAls WiTH sEvere MenTal retaRdation makE thE tRansition froM PrEsymbolic, dIstAl gesture comMunIcatioN tO reFErentIal SymboLic comMUnicatIon (Aim 4); and AcROss one OR more otHER cRitiCal cusps
 arriving at the identifie d cusps at  a fa ste r p ac e. S peci fic aims 4 and 5 ar e to determine whether  spec if i c in t er venti on proc e du r e s a re  e ffe ct i ve  in h elp ing ind ividuals w ith  s evere mental re tardationmak e the transi tio n from  p res y mboli c,dista l gest u re com municatio nt o refe r entials y mb olic  communication (A i m4 ); and acrossone or  m o re o the r c ritical cu sp s
 arriving_at the_identified cusps at a_faster pace._Specific_aims 4_and_5 are to_determine whether specific_intervention procedures are effective_in helping individuals_with_severe mental retardation make the transition from presymbolic, distal gesture communication to referential symbolic_communication_(Aim 4);_and_across_one or more other critical_cusps