No abstract

Vivid dreaming often conjures-up imaginary novel images during the sleep.

Traditionally, the neurological correlates of IQ test questions are characterized qualitatively in terms of 'control of attention' and 'working memory.' In this report we attempt to characterize each IQ test question quantitatively by two factors: a) the number of disparate objects that have to be imagined in concert in order to solve the problem and, b) the amount of recruited posterior cortex territory. With such a classification, an IQ test can be understood on a neuronal level and a subject's IQ score could be interpreted in terms of specific neurological mechanisms available to the subject.Here we present the results of an analysis of the three most popular nonverbal IQ tests: Test of Nonverbal Intelligence (TONI-4), Standard Raven's Progressive Matrices, and Wechsler Intelligence Scale for Children (WISC-V). Our analysis shows that approximately half of all questions (52±0.02%) are limited to mental computations involving only a single object; these easier questions are found towards the beginning of each test. More difficult questions located towards the end of each test rely on mental synthesis of several disparate objects and the number of objects involved in computations gradually increases with question difficulty. These more challenging questions require the organization of wider posterior cortex networks by the lateral prefrontal cortex (PFC). This conclusion is in line with neuroimaging studies showing that activation level of the lateral PFC and the posterior cortex positively correlates with task difficulty. This analysis has direct implications for brain pathophysiology and, specifically, for therapeutic interventions for children with language impairment, most notably for children with Autism Spectrum Disorder (ASD) and other developmental disorders. Keywords AbbreviationsNOB score = number of objects score PCT score = posterior cortex territory score

Prefrontal synthesis (PFS) is defined as the ability to juxtapose mental visuospatial objects at will. Paralysis of PFS may be responsible for the lack of comprehension of spatial prepositions, semantically-reversible sentences, and recursive sentences observed in 30 to 40% of individuals with autism spectrum disorder (ASD). In this report we present data from a three-year-long clinical trial of 6454 ASD children age 2 to 12 years, which were administered a PFS-targeting intervention. Tablet-based verbal and nonverbal exercises emphasizing mental-juxtaposition-of-objects were organized into an application called Mental Imagery Therapy for Autism (MITA). The test group included participants who completed more than one thousand exercises and made no more than one error per exercise. The control group was selected from the rest of participants by a matching procedure. Each test group participant was matched to the control group participant by age, gender, expressive language, receptive language, sociability, cognitive awareness, and health score at first evaluation using propensity score analysis. The test group showed a 2.2-fold improvement in receptive language score vs. control group (p < 0.0001) and a 1.4-fold improvement in expressive language (p = 0.0144). No statistically significant change was detected in other subscales not targeted by the exercises. These findings show that language acquisition improves after training PFS and that a further investigation of the PFS-targeting intervention in a randomized controlled study is warranted.

No abstract

Here we report the results of the subgroup analyses of an observational cohort of children whose parents completed the Autism Treatment Evaluation Checklist (ATEC) over the period of several years. A linear mixed effects model was used to evaluate longitudinal changes in ATEC scores within different patient subgroups. All groups decreased their mean ATEC score over time indicating improvement of symptoms, however there were significant differences between the groups. Younger children improved more than the older children. Children with milder ASD improved more than children with more severe ASD in the Communication subscale. There was no difference in improvement between females vs. males. One surprising finding was that children from developed English-speaking countries improved less than children from non-English-speaking countries.

In order to grasp the difference between "the cat on the mat" and "the mat on the cat," understanding the words and the grammar is not enough. Rather it is essential to visually synthesize the cat and the mat together in front of the mind's eye to appreciate their relations.This type of voluntary imagination, which involves juxtaposition of mental objects is conducted by the prefrontal cortex and is therefore called Prefrontal Synthesis (PFS). While PFS is essential for understanding of complex language, its acquisition has a strong experience-dependent critical period putting children with language delay in danger of never acquiring PFS and, consequently, not mastering complex language comprehension. In typical children, the timeline of PFS acquisition correlates with vocabulary expansion. Conversely, atypically developing children may learn hundreds of words but never acquire PFS. In these individuals, common tests of intelligence based on vocabulary assessment may miss the profound deficit in PFS. Accordingly, we developed a 5-minute test specific for PFS -Linguistic Evaluation of Prefrontal Synthesis or LEPSand administered it to 50 neurotypical children, age 2 to 7 years (4.1±1.3) and to 23 individuals with impairments, age 8-21 years (16.4±3.0). All neurotypical children older than 4 years received the LEPS score 7/10 or greater indicating good PFS ability. Among individuals with impairments only 9 of 23 (39%) received the LEPS score 7/10 or greater. LEPS score was 90% correct in predicting high-functioning vs. low-functioning class assignment in individuals with autism, while full-scale IQ score was only 50% correct.

We analyzed all published reports of individuals not exposed to syntactic language until puberty: two feral children, who grew up without hearing any language, and eight deaf linguistic isolates, who grew up communicating to their families using homesign or kitchensign, a system of gestures which allows them to communicate simple commands but lacks much in the way of syntax. A common observation in these individuals is the lifelong difficulty understanding syntax and spatial prepositions, even after many years of rehabilitation. This debilitating condition stands in stark contrast to linguistic isolates' performance on memory as well as semantic tests: they could easily remember hundreds of newly learned words and identify previously seen objects by name. The lack of syntactic language comprehension in linguistic isolates may stem from inability to understand words and/or grammar or inability to mentally synthesize known objects into novel configurations. We have previously shown that purposeful construction of novel mental images is the function of the lateral prefrontal cortex (LPFC) ability to dynamically control posterior cortex neurons (Vyshedskiy et al. 2017 posterior cortex territory that needs to be recruited by the LPFC and b) the number of disparate objects that have to be combined together by the LPFC in order to answer the test question. According to our analysis, linguistic isolates performed well in all tests that did not involve the LPFC control of the posterior cortex, showed decreasing scores in tests that involved greater recruitment of the posterior cortex by the LPFC, and failed in tests that involved greatest recruitment of posterior cortex necessary for mental synthesis of multiple objects. This pattern is consistent with inadequate frontoposterior connections in linguistic isolates. We discuss implications of these findings for the importance of early syntactic language exposure in formation of frontoposterior connections.