Human iN cells were fixed in ice-cold 4% paraformaldehyde in phosphate-buffered saline (PBS) and permeabilized using 0.2% Triton X-100 in PBS at room temperature. Cells were then washed three times in PBS and blocked in 4% bovine serum albumin (BSA) with 1% normal goat serum (blocking buffer) in PBS at room temperature. Primary antibodies were diluted in blocking buffer and incubated overnight at 4 °C. The next day, samples were washed five times with PBS at room temperature and incubated with secondary antibody in blocking buffer at room temperature. Following incubation, coverslips were washed three times in PBS, with a final wash in deionized water. Coverslips were then mounted onto glass slides with Mounting Media containing DAPI (Fluoroshield, catalog# F6057). Primary antibodies used include chicken anti-MAP2 (Sigma Aldrich AB5543, 1:1000), rabbit anti-Synapsin (E028, 1:3000), mouse anti-Oct 4 (Millipore Sigma MAB4401, 1:2000), mouse anti-Tra-1–60 (Millipore Sigma MAB4360, 1:1000), and mouse anti-Gad-67 (Abcam ab26116, 1:500). Secondary antibodies used included goat anti-chicken IgY-Alexa Fluor 546 (Invitrogen A-11040, 1:500), goat anti-rabbit IgG-Alexa Fluor 488 (Invitrogen A-31556, 1:500) and goat anti-mouse IgG-Alexa Fluor 546 (Invitrogen
