text: PARENTS and babies seem to love infant walkers, parents for the baby-tending and entertainment value of these wheeled seats and babies for being able to scoot around the house in them long before they can walk and even before they can crawl. Many parents believe that infant walkers foster the development of the motor skills needed for walking and provide mental stimulation by allowing the baby to explore a broader environment.
  
  But in recent years, walkers have come under increasing attack as safety hazards, responsible for as many as 25,000 visits a year to hospital emergency rooms for the treatment of injuries like skull fractures, concussions, broken limbs and burns. Many experts have been pressing for a ban on infant walkers, which can be found in up to 92 percent of homes with infants.
  
  Now a researcher at Case Western Reserve University in Cleveland has found that contrary to common parental beliefs, infant walkers are likely to impair -- not foster -- an infant's motor and mental development. Dr. A. Carol Siegel, an experimental psychologist and postdoctoral fellow at the university, tracked the motor and mental skills of 109 infants 6 to 15 months old to determine the developmental effects of spending part of each day in a walker. The study was conducted at the State University of New York at Buffalo with Dr. Roger V. Burton, a developmental psychologist, and has not yet been published.
  
  In an interview, Dr. Siegel emphasized that all the babies she studied had been within normal ranges on tests but that those who used walkers had been relatively delayed in their motor and mental development. The babies were not followed long enough to know whether the ones who used walkers eventually caught up.
  
  Infant walkers are seats hanging from frames that allow a baby to sit upright with the legs dangling and feet touching the floor. They have tray tables in front and wheels on the base. Infants are typically placed in walkers between the ages of 4 and 5 months, and use them until they are about 10 months old.
  
  Dr. Siegel said she had undertaken the study after she had watched a niece navigate in a walker and had recalled an experiment done in the 1960's involving kittens fitted with conical collars that prevented them from seeing their limbs. When the collars were removed, the kittens were unable to visually guide their legs for a time; for example, they could not hit a dangling ball of string with their feet. Dr. Siegel wondered whether infant walkers, especially those with trays that block babies' views of their feet, would have a similar deleterious effect.
  
  Half the babies in the study did not use walkers. The other half spent, on average, two and a half hours a day in a walker. Some of them spent as little as 30 minutes in a walker but others spent as long as six and a half hours. Most of the babies studied came from relatively affluent homes and had parents who had some education after high school.
  
  Dr. Siegel divided the infants into three groups according to their age at the outset of the study -- 6 months, 9 months and 12 months -- and assessed their motor and mental skills at the start of the study and again three months later. She determined when and for how long the babies used walkers and tested their language, memory, perception and motor skills with the Bayley Scales of Mental and Motor Development, a well-accepted measuring device. She also asked the parents to record when the babies mastered various skills like crawling and walking.
  
  On average, infants who did not use walkers sat at 5 months, crawled at 8 months and began to walk in their 10th month, while babies who used walkers that blocked their views of their feet first sat near the end of their 6th month, crawled at 9 months and walked at almost 12 months. Babies whose walkers permitted them to see their feet sat and crawled at an age midway between the other two groups. In addition, babies in walkers showed some abnormalities in posture and gait when they first started walking, although these abnormalities soon corrected themselves.
  
  Mental skills were also less developed among the babies who used walkers. Mental scores averaged 113 for those using walkers that blocked views of the feet, while babies who did not use walkers had an average score of 123. Babies using walkers that allowed them to see their feet averaged 116, between the other two groups. The average score on this test nationally is 100. The higher scores of the babies in the study reflected their relatively high socioeconomic backgrounds.
  
  ''While parents tend to think of walkers as an enriching experience for their babies, I see them as deprivation,'' Dr. Siegel said. ''Infants learn by exploring objects in their environment. They drop things, then go after them by reaching, rolling on the floor or crawling. But while a baby in a walker could motor over to things, she can't get to the things she wants to obtain. If she drops something, she can't pick it up. And if babies use a walker after they start to crawl, it deprives them of the ability to freely explore their environment, and this can adversely affect cognitive development.''
summary: PARENTS and babies seem to love infant walkers, parents for the baby-tending and entertainment value of these wheeled seats and babies for being able to scoot around the house in them long before they can walk and even before they can crawl. Many parents believe that infant walkers foster the development of the motor skills needed for walking and provide mental stimulation by allowing the baby to explore a broader environment.    But in recent years, walkers have come under increasing attack as safety hazards, responsible for as many as 25,000 visits a year to hospital emergency rooms for the treatment of injuries like skull fractures, concussions, broken limbs and burns. Many experts have been pressing for a ban on infant walkers, which can be found in up to 92 percent of homes with infants.