Which of the following claims are demonstrated by the dichotic listening task in psychological research?

• A. Humans can selectively attend to one auditory stream while ignoring competing information.
• B. All incoming auditory information is processed equally regardless of attention.
• C. Selective attention is impossible when presented with two different auditory messages.
• D. The dichotic listening task proves that memory for unattended information is always perfect.

Answer: (A)

Verified step by step guidance

1. Step 1: Understand the dichotic listening task, which involves presenting two different auditory messages simultaneously, one to each ear, and asking the participant to focus on and repeat (shadow) only one message.
2. Step 2: Recognize that the main purpose of the task is to study selective attention — how well a person can focus on one auditory stream while ignoring the other.
3. Step 3: Analyze the claims by comparing them to what the dichotic listening task demonstrates: it shows that humans can selectively attend to one message and filter out the other, rather than processing all information equally.
4. Step 4: Note that the task disproves the idea that all incoming auditory information is processed equally, and it also shows that selective attention is indeed possible, contrary to some claims.
5. Step 5: Understand that memory for unattended information is typically poor or incomplete in this task, so the claim that memory for unattended information is always perfect is not supported.