Sensory processing difficulties, also known as Sensory Processing Disorder (SPD), refer to the challenges some children face in responding to sensory stimuli in a typical way. This can involve hypersensitivity (over-responsiveness) or hyposensitivity (under-responsiveness) to various sensory inputs like touch, sound, light, taste, and movement. These difficulties can significantly impact a child's daily functioning, emotional regulation, and social interactions.