Human Brain Development Timeline

Human Brain Development Timeline

Research on the development of the human brain has seen an upturn in the past 15 years due to novel imaging techniques such as MRI and fMRI.

In the 1950s, animal research showed development in the sensory regions after birth. During sensitive periods, the environment plays a major role in normal development.

This research indicated that from early postnatal time through the next several months or years, the brain went through synaptogenesis followed by synaptic pruning which represent the creation and elimination of synapses during growth.

In the 1960-70s, studies were done on human brains to reveal development past the early childhood years, especially in the prefrontal cortex. This was identified by the process of myelination where the developed regions axons' were myelinated first while the association areas were still able to develop through adolescence.

Synaptic reorganization takes place most predominantly during childhood and adolescence. During these periods the brain becomes sensitive to change which allows it to develop in unique ways dependent upon the individuals age, gender, and environment along with many other variables.

The concept of "self-organization" indicates that the brain actually organizes itself based on the individuals experiences.

In 2012, a team of scientists created a statistical model that could predict the age of an individual under the age of 20 from an MRI scan with 92% accuracy. The model measures 231 biomarkers of brain anatomy and was constructed with data from 885 people. This work provides a uniquely holistic view of adolescent brain development and suggests that the responsible processes are more strongly genetically pre-programmed than is typically thought.