Autism: Intense World Theory, High-intelligence Imbalance Hypothesis, Social Motivation Hypothesis, And Interconnectivity Theory
Autism is a developmental disorder characterized by the individual’s struggle with social skills, verbal and non-verbal communication, and repetitive actions. With the onset occurring before the age of three, the disorder still remains a great mystery for modern science. Specifically, the troubling dichotomy between an autistic’s remarkable abilities and their curious incapacities. Through understanding the basic underpinnings of the disorder, the Intense World Theory, High-Intelligence Imbalance Hypothesis, Social Motivation Hypothesis, and Interconnectivity Theory provide some possible explanations behind this great paradox of autism.
A fundamental component that drives autistic symptoms is the disconnectivity between some brain regions and hyperconnectivity in the local areas. The Intense World Theory proposes that these neighboring circuits become hyper-reactive and hyper-plastic, and thus further speculates that they become autonomous and “memory trapped.” This leads to hyper-attention, hyper-perception, hyper-memory, and hyper-emotionality. When it comes to hyper-memory, animal models have shown that at two weeks old – while the presynaptic Long-term Potentiation (LTP) was normal – there was an enhanced form of postsynaptic LTP in both neocortical layers 2/3 and layer 5 pyramidal neurons for the rats with autism symptoms. The models also have shown an increased rate at which neurons connect and disconnect for these eats. NMDA receptors may be responsible for this idiosyncratic hyper-plasticity. In the “autistic” rats, NMDA subunit receptors NR2A and NR2B were more than two-times overexpressed. This explains how in one study the “autistic” rats were able to better memorize the differences between multiple crevices compared to the normal group. These studies demonstrate that the hyper-plasticity of the microcircuits may be responsible for the exceptional memory and savant skills seen in autistic individuals.
However, this enhanced memory indicates a heightened fear memory. In one model, rats were conditioned to fear a certain tone. The “autistic” rats showed amplified conditioned responses and, even three months after conditioning, they exhibited “contextual fear memories.” Unlike the controls, their fear also generalized to non-fear tones and overall was more persistent and harder to extinguish. The evidence in these animal models suggests that autistic individuals store fear memories in a magnified and obstinate way. They also overly generalize learning and have difficulty extinguishing fear of a particular stimulus. Enhanced fear processing could be the underpinnings for the stereotypical behaviors of inappropriate reactions to the environment, unusual and sudden anxiety outbursts, lack of social IQ, and phobias. For autistics, the overgeneralization limits the number of stimuli deemed “safe” and, when combined with the difficulty to extinguish, may lead to an “intense world” for these individuals. Moreover, the theory believes this indicates that the lack of social interaction in Autism is not due to insufficient social and emotional cues but rather a reaction to overly strong smaller signals who are hard to ignore, are excessively processed, and remembered with frightening potency. Social avoidance such as little eye gaze, social withdrawal, and the lack of communication could be a defense mechanism and refuge after the initial experience of over-awareness of both sensory and social components of the environment.
The Intense World Theory, additionally, elaborates why autistic patients have trouble in some forms of processing while showing exceptional abilities in other areas. It holds that this nature is better explained by excessive autonomous microcircuit rather than deficits in long-range connectivity. The hyper-plasticity and strong consolidation of memories during development lead to the dominance of further strengthening the earliest features and avoidance of processing newer or other features. This selectivity develops hyper-autonomous and overly selective circuits resulting in a neocortex divided into independent units who are difficult to control and coordinate. Moreover, a signature characteristic of autism in children is enlarged brain size. The brain is growing prematurely at an intense rate leading to enhanced functionality. However, while scans have shown increased white matter at age 2-3, the white matter in older autistic children was the same as normal children the same age. This alludes to the idea that the brain might get overwhelmed by the fast growth and at some point starts to regress and take refuge in a “highly specialized cocoon.” This could explain why autistic children may exhibit incredible skills in one area and extremely weak capacities in another domain.
On the other hand, the High Intelligence Imbalanced Hypothesis draws on another reason for the drastic differences in abilities in autism. The theory believes that increase the risk of autism is underlined by its genetic and phenotypic association with high intelligence. It demonstrates that there are positive correlations between the alleles for autism and alleles for high intelligence, such as DUF 1220; both exhibit similar features such as an enlarged brain, fast brain growth, increased sensory and visual-spatial abilities, enhanced synaptic function, increased attention focus, more deliberative decision making, and interest in STEM. However, autism has long been categorized as a condition of low intelligence by most standard tests. One test, the Verbal Perceptual Rotational Model of Intelligence (VPR Model), provides great insight into why there’s this dissonance. Its three foundational pillars – verbal, perceptual, and rotational – each relate to different parts of the brain: verbal fluency and knowledge correlate with the left hemisphere, perceptual and spatial abilities with the right, and mental rotation of objects or people is related to the corpus callosum and going between hemispheres. Consequently, the test also has demonstrated evidence that there is a tradeoff between cognitive abilities. It has shown that there is an inverse relationship between image rotation and verbal abilities and also focal attention and diffuse attention. An intriguing observation is that this dichotomy also represents sex differences as males are better at image rotation and females are generally better in verbal and diffuse attention abilities. This evidence is important to note, especially since there is a 5:1 male to female ratio in autism. With a plethora of data demonstrating that in autism there is a decrease in verbal abilities but enhanced focal attention, perceptual and spatial abilities, and ability in the non-rotational features of the mental rotation tasks, the VPR model illustrates that autism reflects the extremes of typical tradeoffs in intelligence and is an altered expression of adaptive cognitive variations. Therefore, autism is a manifestation of an extreme imbalance of intelligence. Another set of evidence that shows reinforces autism as an imbalance of intelligence is that fluid intelligence is enhanced in autism and crystallized intelligence is reduced.
These tradeoffs are further supported when looking at genetics. Four studies were conducted to test the overlap between alleles associated with risk of autism and alleles for high intelligence. All four found a strong significant relationship with genetically-based risk of autism and intelligence. When considering schizophrenia – the condition that often represents the psychiatric, psychological, neurological, and genetic foil of autism – there is a negative genetic correlation between schizophrenia risk and measures of intelligence. This complements the results of the VPR model where autism and schizophrenia appear on opposite extremes. The genetic and phenotypic correlations between autism and intelligence suggest that the risk for autism could be dictated by high but lopsided components of intelligence.
Moreover, in addition to similar phenotypes and genetic basis, intelligence and autism share two other aspects. The first one is sensory abilities. There is a proven positive correlation between sensory abilities and sensory discrimination skills with high intelligence. This dovetails the abundant amount of evidence that sensory discrimination and acuity are enhanced in autism. Support for this is the EFT, the Embedded-Figures Test, which is a visual-spatial test. It has demonstrated that when it comes to speed of processing, accuracy, or both autistics are superior to controls. The test’s results have indicated that there is a connection between visual sensory abilities and sensory discrimination with intelligence. However, for individuals with autism, this increase in sensory abilities are enhanced to the point of imbalance with other aspects of IQ. According to the Parietal Frontal Integration Theory (P-FIT) mode of intelligence, the first developmental stage of intelligence circuitry is processing sensory information, which resides mostly in the occipital and parietal regions. As the brain tries to build circuits in other brain areas – especially those that help symbolism and abstraction – the hyper-functioning of the sensory processing region makes integration with the rest of the brain dysregulated. The P-FIT model also complements the imbalance exhibited in the VPR model. It demonstrates that in order to have “efficient” patterns of brain connectivity there has to be an optimal mix of short and long-range connects. However, autistics primarily have increased short-range circuits. This intensification comes at the expense of long-range connections, which consequently represent a constraint for general intelligence in autism. Yet, the enhancement of these microcircuits results in heightened auditory pitch perception, increased levels of perception, attention, and memory to the point that they interfere with social functioning.
The second factor is the positive link between both intelligence and autism with high socioeconomic standing. There have been well documented positive genetically-based associations between high intelligence and socioeconomic status. This dovetails with the risk for autism as positively associated with high parental intelligence and high economic status; Kanner first observed this in 1943 when he saw that autistic children “all come from highly intelligent families” with high levels of educational, socioeconomic, and occupational achievement.
The High Imbalanced Hypothesis explains that there is a fine balance for high intelligence to “go right.” It outlines that the risk of higher intelligence means a higher risk for polarity; If the scales are tipped too far to one side, then an imbalance exists and consequently a chance of autism. This “high imbalance” of intelligence could thus clarify why there is this disparity between autistic’s incredible abilities and hindering attitudes.
Two other theories that could explain the impairments in autism are the Social Motivation Hypothesis and the Interconnectivity Theory. The social motivation hypothesis theorizes that there is an important impairment in social functioning and dysfunction in the corresponding brain system. Autistic individuals experience a decrease in social drive leading to a lack of attention to people. Since these systems are being underused and are lacking reinforcement, these “experience-driven” brain systems fail to be specialized and develop. According to one finding, autistics have impaired face recognition and discrimination. Other studies have suggested autistics may have impairments for understanding the facial expression of emotion. Interconnectivity Theory proposes that in autism there is dysfunctional processing of complex information. This is due to the fact that local connectivity is enhanced and long-range connectivity is reduced in autism. Simple processing is related to local circuits, rather the information that is spread out and thus more complex require good long-range connectivity. Moreover, social interaction requires higher-levels of processing and that might explain why autistics struggle when it comes to social situations.
The Intense World Theory, High Imbalance of Intelligence Hypothesis, the Social Motivation Theory, and the Interconnectivity Theory provide possible theses to decode the great oxymoron of autism. The Intense World Theory speculates that the hyperconnectivity of local circuits exhibited in autism results in hyper-plasticity and a strong consolidation of memories during development. This leads to the brain overly strengthening the earliest regions – such as sensory information in occipital and parietal lobes – before it gets too overwhelmed and avoids processing newer other features. The brain starts to regress and resemble a “high specialized cocoon.” On the other hand, the High Imbalance of Intelligence Hypothesis attributes the paradox of autism to an uneven distribution of high intelligence. Shown through the VPR model, there are tradeoffs between various bits of intelligence. Thus, high intelligence is a very precise equilibrium. However, if the scales favor one way of intelligence far more, there is an imbalance and may result in autism. The hypothesis supports this claim by indicating that there are many genetic and phenotype correlations between high intelligence and autism. It postulates, therefore, that a risk of high intelligence is a risk of autism. Unlike the other two explanations, the Social Motivation Theory believes that the impairments in autism are due to lack of social drive and therefore social learning is not continuously being reinforced. Conversely, the Interconnectivity Theory accredits the great abilities and disabilities in autism to the reduction of long-range connectivity and dysfunctional processing of complex information. While these four hypotheses may differ in various accounts, they all provide helpful windows into understanding the great mystery of autism.