There are 25 memory collectibles, each chapter has 5 memory collectibles.
To collect the memories you must hold L2 and X.
Chapter 1
Memory: Riley Letter - 0:00
Memory: Crack - 0:36
Memory: Business Card - 1:08
Memory: Helmet - 1:51
Memory: Phone - 2:24
Chapter 2
Memory: Button - 3:03
Memory: Rent Check - 4:04
Memory: Umbrella - 4:25
Missable: Bird Spotting - 4:52
Missable: Found Dog! - 6:00
Memory: Gummies - 6:50
Memory: T-Shirt - 7:26
Chapter 3
Missable: Earworm Squasher - 8:11
Memory: Bomber Jacket - 9:33
Memory: Dollar - 10:00
Memory: Appointment Slip - 10:30
Memory: Old Paper - 11:11
Memory: Valkyrie's Dish 11:53
Chapter 4
Memory: Pressed Rose - 12:27
Memory: Drum Kit - 12:56
Missable: Exactly 731 - 13:30
Memory: Microphone - 14:48
Memory: Polaroid - 15:23
Memory: CIT Sticker - 16:01
Chapter 5
Memory: Mom's Keys - 16:38
Memory: Business Card - 17:08
Memory: Guitar Strings - 17:55
Memory: Pendant - 18:35
Memory: Bomber Jacket - 19:43