People's younger years provide time for a wide range of experiences - some positive, and others negative. As children grow older, they have an opportunity to meet interesting new people, engage in different activities and see things that can influence their outlook on life. Others have less control over what happens to them during their youth and become the victims of misfortune or grow up facing great hardship.

No matter what type of childhood people have, it is clear that what they experience growing up can shape the types of adults they will eventually become. Beyond influencing their personalities and beliefs, research shows that what individuals go through in adolescence may also impact their IQ.

Too much television early on can influence academic performance
Some parents may not think too much about the impact exposure to television can have on their young children, but based on research from Linda S. Pagani of the Université de Montréal and colleagues, watching TV too early could be detrimental in the long run.

After studying 1,314 children who were exposed to TV at 29 months of age, the researchers found a connection between this early activity and academic problems by the time they reached the fourth grade. Overall, for every additional hour of TV these students watched at 29 months, there was a 6 percent unit decrease in mathematical achievement and a 7 percent unit decrease in classroom engagement.

In addition, too much TV at 29 months was also linked to an unhealthy diet and a higher chance of victimization by classmates. Both factors could influence children's mood, which in turn, can impact their school performance. Ultimately, this research shows that something as simple as exposure to TV early in life can have long-lasting ramifications on people's development.

Memories of childhood hunger not as detrimental for some people
No parent wants to see his or her child growing up hungry, but unfortunately, this is the case for too many families. One might assume that individuals who do not have food to eat during childhood would have more IQ problems later in life than those who did not go without regular meals. However, based on research from Lisa Barnes, a cognitive neuropsychologist at Rush University Medical Center and her colleagues, this was not the case, at least for African Americans over the age of 65 who participated in their study.

Over the course of their study, the researchers worked with 6,100 individuals who were at least 65 years old, according to Discovery News. Using information from interviews and cognitive tests, the researchers learned that African American participants who remembered going hungry were less likely to see their mental abilities decline with age. This, in turn, shows that childhood adversity is more protective than detrimental.

"I think the big-picture take-home message is that early experiences matter," said Tené Lewis, a psychosocial epidemiologist at Emory University's Rollins School of Public Health in Atlanta, as quoted by the news source. "But we’re not quite sure how or why."

Using marijuana could lower IQ
Growing up, children are often told not to use drugs by their parents and teachers. Based on available research, these authority figures are right, as frequent marijuana use during individuals' teenage years can do enough damage to reduce their IQ over time, CBS News reported.

"Marijuana is a very dangerous drug to the brain, particularly in adolescence, and it's also a carcinogen, so it's not healthy for adults either," said Harris Stratyner, vice president of Caron Treatment Centers' New York Clinical Regional Services, as quoted by the news outlet. "It's much more dangerous than we've ever given it credit for."

No matter what activities children engage in, their parents should remember it may be possible to monitor the development of their cognitive function through assessments like an IQ test for kids.