Which condition is characterized by impaired memory and cognitive function without loss of consciousness?

Dementia is characterized by a gradual decline in cognitive abilities, including memory, reasoning, and communication skills, without an alteration in consciousness. Individuals with dementia may experience difficulty in performing daily activities, changes in mood, and impaired judgment, but they remain aware of their surroundings, in contrast to conditions like delirium where consciousness is affected.

Dementia typically progresses over time and is often associated with neurodegenerative diseases such as Alzheimer's disease, vascular dementia, and others. The preserved level of consciousness is a key distinguishing feature, as it differentiates dementia from other cognitive impairments where awareness may be compromised.

In the context of other conditions, delirium involves acute confusion and fluctuating levels of consciousness, while depression can lead to cognitive dysfunction but is primarily a mood disorder. Psychosis involves a loss of contact with reality and may include delusions or hallucinations, which also do not align with the specific cognitive impairment characterized in dementia.