How do you define adulthood? It's a difficult question because that delicate brain of yours stays squishy well after you start paying your own rent. https://www.youtube.com/learnhowtoadult Hosted by: Brit Garner ---------- Support SciShow by becoming a patron on Patreon: https://www.patreon.com/scishow ---------- Dooblydoo thanks go to the following Patreon supporters: Kevin Bealer, Mark Terrio-Cameron, KatieMarie Magnone, Patrick Merrithew, D.A. Noe, Charles Southerland, Fatima Iqbal, Sultan Alkhulaifi, Nicholas Smith, Tim Curwick, Alexander Wadsworth, Scott Satovsky Jr, Philippe von Bergen, Bella Nash, Chris Peters, Patrick D. Ashmore, Piya Shedden, Charles George ---------- Looking for SciShow elsewhere on the internet? Facebook: http://www.facebook.com/scishow Twitter: http://www.twitter.com/scishow Tumblr: http://scishow.tumblr.com Instagram: http://instagram.com/thescishow ---------- Sources: https://www.nytimes.com/2016/12/21/science/youre-an-adult-your-brain-not-so-much.html http://www.cell.com/neuron/pdf/S0896-6273(16)30809-1.pdf https://academic.oup.com/cercor/article-lookup/doi/10.1093/cercor/bhp118 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3131482/ http://fablab.yale.edu/sites/default/files/publications/Cohen%2C%20Breiner%2C%20Steinberg%2C%20et%20al%20%282016%29%20When%20is%20an%20adolescent%20an%20adult.pdf http://www.health.harvard.edu/mind-and-mood/can-you-grow-new-brain-cells https://www.researchgate.net/publication/313284144_At_risk_of_being_risky_The_relationship_between_brain_age_under_emotional_states_and_risk_preference https://www.scientificamerican.com/article/why-is-synaptic-pruning-important-for-the-developing-brain/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3055433/ https://www.ncbi.nlm.nih.gov/pubmed/21906988 https://blogs.scientificamerican.com/brainwaves/know-your-neurons-what-is-the-ratio-of-glia-to-neurons-in-the-brain/