As far as I understand it, the latter provides information needed for the former. It's possible to have deficits in either or both:
1) Hearing loss in specific volume/frequency notches instead of loss strictly at the high/low end (sometimes referred to as "hidden hearing loss", which is more a statement about the capabilities of routine screenings than it is a statement about the nature of the hearing loss)
2) Deficits in attention regulation, which are seen in numerous conditions (most obviously ADHD, but also autism spectrum, PTSD, traumatic brain injury, schizophrenia and "schizophrenia-like" conditions, and some forms of dementia)
It’s actually hard to separate the two. On the one hand, the hearing aid might not faithfully reproduce cues that let you separate different sources. On the other, “higher” brain areas can modulate early sensory areas (maybe even the cochlea) to make sounds relevant to your current behaviors more salient while attenuating irrelevant signals.
1) Hearing loss in specific volume/frequency notches instead of loss strictly at the high/low end (sometimes referred to as "hidden hearing loss", which is more a statement about the capabilities of routine screenings than it is a statement about the nature of the hearing loss)
2) Deficits in attention regulation, which are seen in numerous conditions (most obviously ADHD, but also autism spectrum, PTSD, traumatic brain injury, schizophrenia and "schizophrenia-like" conditions, and some forms of dementia)