Excel MACROS - VBA Language: merging multiple workbooks into one

Hi everyone,

I am unfamiliar with the VBA language and I have got this current issue. I have a folder with 51 Excel files that represent 51 participants that have been tested. In each file there are, among others, derived variables from a cognitive test. In all these excel files, those derived variables are between cell J4 and cell R4, included. I would like to know if there's a syntax I can use to copy the array of the derived variables for each of the 51 participants into a comprehensive excel workbook.

Thank you for your help.