Critical Period Hypothesis

Early childhood development occurs in stages and may be influenced by the individuals’ environment. After reading “Critical-Period Hypothesis” by James V. McConnell (Understanding Behavior, Copyright 1974), it raised some questions in my mind regarding early childhood development such as how a young child’s speech develops, how they learn to walk and how they learn to use the bathroom. All three developments normally occur by a certain age. However in my experience I know that these developments can be delayed or not occur normally due to environmental obstacles. I have even seen cases in my personal experience that delays occurred due to emotional problems. In the Critical-Period Hypothesis, there is some debate as to whether humans can “catch up” if there is a delay in development. However, as the article states that by being born without strong innate behavior patterns (such as imprinting), we seem better able to adjust and survive, or “catch up”. It also mentions that children appear to have a tendency to imitate behaviors. I was an employee of New York State as a Developmental Aide for 20+ years. I worked with developmentally disabled children, and had extensive training on the cause and effects of mental retardation. I was amazed to learn that many of the patients had become “environmentally retarded”. I had always thought that someone with those types of disabilities must have been born that way. I was saddened to find out that several years ago many normal young patients were born into the institution or made to live there at very young ages. Many were malnourished, mistreated, and had no attention paid to them for days and years at a time. The young children were housed with older patients that had many developmental problems such as speech, hearing, incontinence, non-ambulatory, etc. After many years of living in this environment, the young patients also developed the same developmental problems. In recent years, there has been a movement to take care of this disabled population in a more humane manner. The patients now treated as individuals are no longer in an institutional setting. There has also been progress made with some individuals that have become “environmentally retarded” by repetition of new learned behaviors. There has also been some progress due to drug therapy. However, many individuals still exhibit the developmentally disabled traits to no avail. It seems that the young patients’ developmental disabilities were due to the extreme environment that they lived in. In addition, many of their delays (speech, ambulation, toilet training) were in part due to “imitating” behaviors. There was some progress made after years of repetitive conditioning, but not for all. I have to wonder if the rehabilitation process had begun sooner when the patients were younger if it would have been more beneficial. I believe that Critical-Period Hypothesis to be valid, and should be studied more in depth.