According to DSM and ICD,
Borderline intellectual functioning refers to estimated intelligence quotient scores within the 70 to 75 range on an intelligence test with an average of 100 and a standard deviation of 15.
Borderline intellectual functioning (BIF) is characterized by heterogeneous cognitive difficulties, with an intelligence quotient (IQ) between 70 and 85 points, and a failure to meet the developmental and sociocultural standards for personal independence and social responsibility required in daily life.
The DSM-IV classifies mental retardation into four stages based on severity: mild (IQ score of 50-55 to approximately 70), moderate (IQ score of 30-35 to 50-55), severe (IQ score of 20-25 to 35-40), and profound (IQ score of less than 20-25).
Persons with a mild intellectual disability (MID; intelligence quotient (IQ) range 50–69) or borderline intellectual functioning (BIF; IQ range 70–85) are vulnerable for problems in different domains.
Signs of Borderline Intellectual Functioning
Difficulty adapting to changes or learning new skills. Difficulty achieving independent living, executing daily life activities, and participating with others in social situations. Difficulty managing emotions and aggression, with moods swings and low frustration tolerance.
A full-scale IQ score of around 70 to 75 indicates a significant limitation in intellectual functioning. 2. However, the IQ score must be interpreted in the context of the person's difficulties in general mental abilities.
Can IQ change with age? Yes. However, there is heavy debate over exactly how IQ and intelligence change with age. Studies have demonstrated that a person's fluid intelligence tends to decrease starting in their late 20s, while their crystallized intelligence tends to increase as they grow older.
There are different ways to measure IQ, but they all rely on similar principles, which means it's possible to increase your IQ with study and training. Improving your IQ can help you to improve your problem-solving and lateral thinking skills, which can be useful in many careers.
The lowest IQ ever would be 0. However, no one has ever scored that. Scores below 75 usually indicate a cognitive disability. Some of the countries with the lowest IQ scores are Liberia, Sierra Leone, and Nepal.
Many individuals with BPD are highly intelligent and are aware that their reactions may seem strong. These individuals often report feeling that emotions control their lives or even that they feel things more intensely than other people.
Borderline personality disorder is a mental illness that severely impacts a person's ability to regulate their emotions. This loss of emotional control can increase impulsivity, affect how a person feels about themselves, and negatively impact their relationships with others.
Research indicates that BPD is linked to above-average intelligence (IQ > 130) and exceptional artistic talent (Carver, 1997). Because your partner with BPD may be exceptionally bright, they digest information and discover answers to problems more quickly than the average person.
In general, an IQ score is defined with a median and mean of 100. Scores above 130 are labeled as above average or “very superior,” while scores under 70 would be considered below average or labeled as “borderline impaired.” Most people have an average IQ between 85 and 115.
To calculate IQ, take a person's mental age, divide it by chronological age, then multiply that number by 100. For example, if a person has a mental age of 12 but is 10 years old, then you'd divide 12 by 10, and multiple that number by 100, which would result in an IQ of 120.
But genetics can explain the wide range of possible IQs too because so many different genes are involved in developing and running a brain. It is possible, for example, to inherit all the higher IQ genes from each parent and leave the lower IQ ones behind. Now the child will be brighter than the parent.
Like, is Elon Musk a genius? It answered, Elon Musk's IQ is reported to be 155, which is very high compared to the average of 100.
A recent study of 1.2 million Swedish military personnel showed that fitness is correlated with intelligence. Moreover, research has consistently linked exercise with improvements in attentional control, processing speed, working memory capacity, and the ability to switch between tasks.
Please note: It is important to be aware that IQ scores do not tend to stabilize, meaning stay the same, until around age 7 or 8 (around the third grade). Therefore, if your child is tested in pre-school or early elementary school, the score may not remain stable through grade school.
IQ peaks and stops increasing at around 20 years of age and then is mostly fixed for life. IQ peaks at around 20-years-old and later effort will not improve it much beyond this point, research finds.
Now we can compare Full Scale (global) IQs for adults of different ages. A clear decline is evident. The mean WAIS-IV IQ is 100 for ages 20-24 and is 99 for ages 25-44. Then it drops to 97 for ages 45-54, to 94 for ages 55-64, to 90 for 65-69, to 86 for ages 70-74 and to 79 for ages 75+.
The IQ of Slow Learner is between 80 and 90 (as per Stern and Terman).
The reality is that IQ results are usually fairly accurate. The psychologist conducting the test ensures this by making sure they don't just look at the test score in isolation. If they're working with a child, for example, they might take into account other factors.
Intellectual disability, formerly called mental retardation (MR) is defined as having an IQ score below 70 whereas an IQ score in the range of 71–84 is termed as “borderline intellectual functioning”.