Large and fast human pyramidal neurons associate with intelligence

Abstract

It is generally assumed that human intelligence relies on efficient processing by neurons in our brain. Although gray matter thickness and activity of temporal and frontal cortical areas correlate with IQ scores, no direct evidence exists that links structural and physiological properties of neurons to human intelligence. Here, we find that high IQ scores and large temporal cortical thickness associate with larger, more complex dendrites of human pyramidal neurons. We show in silico that larger dendritic trees enable pyramidal neurons to track activity of synaptic inputs with higher temporal precision, due to fast action potential kinetics. Indeed, we find that human pyramidal neurons of individuals with higher IQ scores sustain fast action potential kinetics during repeated firing. These findings provide the first evidence that human intelligence is associated with neuronal complexity, action potential kinetics and efficient information transfer from inputs to output within cortical neurons.All rights reserved. No reuse allowed without permission.was not peer-reviewed) is the author/funder, who has granted bioRxiv a license to display the preprint in perpetuity.

Decreased cortical thickness mediates the relationship between premature birth and cognitive performance in adulthood

“…In conclusion, CTh seems to be reduced in some cortical regions in premature‐born adults compared to FT controls due to various mechanisms including dysmaturation of axons and disturbances in dendritic branching and synaptogenesis. These microscopic properties such as dendritic complexity have been linked to intelligence (Goriounova et al, 2018) suggesting that aberrations in CTh may affect cognitive performance.…”

“…In premature‐born adolescents, some studies described a positive relationship between CTh and IQ, which is in line with our findings in adults (Bjuland et al, 2013; Martinussen et al, 2005; Skranes et al, 2012). On a cellular level, intelligence is linked with neuronal complexity as high IQ scores and large temporal CTh are associated with larger, more complex dendrites of human pyramidal neurons (Goriounova et al, 2018).…”

“…Then they decrease through the second decade due to various processes including pruning and increased myelination (Mills et al, 2016; Paus, 2005; Shaw et al, 2008; Sowell et al, 2004; Wilke, Krägeloh‐Mann, & Holland, 2007). Recently, it has been shown that high IQ scores and high temporal CTh scores associate with larger, more complex dendrites of human pyramidal neurons (Goriounova et al, 2018). A positive relationship between general intelligence and CTh has been found in healthy adults (Menary et al, 2013; Narr et al, 2007).…”

Comparing basal dendrite branches in human and mouse hippocampal CA1 pyramidal neurons with Bayesian networks

“…Ref. 36 – 39 ). Certainly, larger angles allow human branches to occupy more volume and thus form more connections and reach further, and might be related to the differences in scale between the human and mouse brains (see also Ref.…”

Gpr158 deficiency impacts hippocampal CA1 neuronal excitability, dendritic architecture, and affects spatial learning

“…Moreover, dendritic complexity appears to increase with evolution and with increasing cognitive demands, with human prefrontal pyramidals exhibiting the largest cortical dendritic complexity (Elston et al, 2001;Mohan et al, 2015). Furthermore, increasing dendritic complexity of human cortical pyramidals appears correlated with increasing intelligence quotient, in a small sample of surgically resected brain tissue (Goriounova et al, 2018). Since the electrophysiological datasets reported here were generated from mice that underwent behavioral assessment (Figure 1 supplement 1), we then averaged the morphology data of all cells collected to generate an overview of dendritic architectures for n=6 animals per genotype (Figure 5a).…”