My brother appeared in the written test for MSc Cognitive Sciences in February 2020. So, I can give you some insight about the same. 

The written test analyses your comprehensive skills i.e. the ability to implement the things you read. The section will contain comprehension questions. It will also include some of the paragraphs or questions based on the Cognitive Science Journals. 

Examination Pattern:

The written test is the same for everyone. 

• It contains 4 questions of comprehensive type and 1 of data interpretation. 
• The total marks for the examination are 25 and the duration is 1 hour. 

Preparation Tips:

• For preparation, you can simply take some random comprehensive type question off the internet and solve it. 
• In his examination, my brother had passages from pathophysiology of neurodegenerative disorders, case-studies on behavioral experiments using VR/AR, etc. 
• The questions are designed in a way that everyone can interpret them.

Be patient and stay motivated. All the best for your exam.