Essay
1st Year Psychology Essays
- Module
- Psychology
- Institution
- Coventry University (West Midlands) (CU)
covering IQ and hereditary, depression and self-harm and Schizophrenia and the effectiveness of antipsychotics
[Show more]
Seller
FollowContent preview
Student id: 5607088 Word Count: 987IQ, hereditary or environmental?
IQ is short for intelligence quotient, it is a number which represents an individual’s
reasoning ability, which is tested via various problem solving tests. The result is compared to
the norm for a person of their age. A genetic influence is apparent towards intellectual
ability (Bouchard and McGue, 1981), however it can be argued that there is an
environmental influence as well, as Rowe, Jacobson and Van den Oord (1999) have
explained. Many studies in this field have been twin studies which enable researchers to
clearly observe the different effects between genes and the environment.
As I mentioned above Bouchard and McGue summarised the results of 111 studies, and it
indicated that there is a hereditary similarity in measured intelligence (IQ). This was shown
by a consistent average correlation with polygenic mode of inheritance. This meta-analysis
shows that there is an association between the variables, therefore genes do contribute to
our IQ. Another study that shows an association is a twin study by Lynn and Hattori (1999).
They looked at 543 monozygotic twins and 134 dizygotic twins. They found that
monozygotic twins had a higher correlation than the dizygotic twins, this shows, as
monozygotic twins share the exact same genes, that genetics do play a big part and also
suggesting, as dizygotic has a lower correlation, that environment doesn’t play as big a part
as genetics when it comes to intelligence. A family design with twins, their siblings and their
parents (Leeuwen, Van den Berg and Boomsma, 2007) is an enhanced way at looking deep
into the hereditary roots. They used a Raven Progressive Matrices test to measure IQ. They
found that parents IQ were similar to one another and with monozygotic twins, correlations
between genes and IQ were higher than first degree relatives. They suggested that a model
proving that this was due to phenotypes was more superior to a model which suggested this
was due to environmental factors. Therefore again showing that genes play a bigger role
than the environment. All this research indicates that genes play a big role to our
intelligence, it is reliable and consistent with regular occurring patterns.
On the other hand Dickens and Flynn (2001) suggest that there is actually a powerful role
for the environment on IQ, environmental effects are short lived in children as they decay
quickly, therefore genes play a role in a child’s IQ. However with adults, IQ is influenced by
the environment in which surrounds them. They showed that enrichment programmes can
boost IQ and this is an environmental effect, such things can develop phenotypic traits. This
therefore suggest that even though there is a genetic link with IQ, it is only prominent in
children and in adults it is the environment that shapes their intelligence. Rowe, Jacobson
and Van den Oord (1999) have similar results. They found that if the parents had more than
a high school diploma, it was more likely the child to have a higher IQ, suggesting it’s
heritable, however in modern society we have institutions that are intellectually stimulating,
such as schools and tutors, which could help increase IQ. However that is not the case with
the working class who may also be well educated, as they live in a different environment to
someone of middle class. They state that children, even with parents with a higher IQ, may
not themselves develop the phenotype if they live in a poor area which lacks intellectually
stimulating institutions. This is a big environmental influence which can override the
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller arthananavaratnam. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for £8.99. You're not tied to anything after your purchase.
Can Stuvia be trusted?
4.6 stars on Google & Trustpilot (+1000 reviews)
52510 documents were sold in the last 30 days
Founded in 2010, the go-to place to buy revision notes and other study material for 14 years now