Honestly, just disappointed.
The idea behind this book is an interesting one. The book is based around memory and the sciences involved etc.
The main character, Jess, completely ruins the novel. Well, Jess and a few other factors. The writing is mediocre. Most of the characters in this story are completely unrealistic. The ending was just dissatisfying and incredibly rushed (did anyone even proofread that part of the book?) The plot holes are huge. Plus the unnecessary plot points to make it well and truly "young adult fiction" [excessive kissing without reason, feminist mottos, forced roadtrips] just felt like they had been squashed into the book to make it readable.
I really could go on, but I dont see the point in spending any more time on this book. I wouldn't recommend.