Part 2 (minus the background  )

Part 2 (minus the background )

Dichotic listening –Donald Broadbent (1958) • One message presented in right ear • Another message presented in left ear • Participants told to only attend/listen to one of the messages and repeat it back as they were hearing it • After, they could not say anything about the unattended message except if it was a male or female voice • Even when a word was used 35 times in the unattended ear

Broadbent’s Filter Model • Donald Broadbent (1958) • First to describe the human as an information processor • Model designed to explain selective attention • Says info passes through 4 stages

Broadbent Filter Model Stages • 1. Sensory store • Holds incoming information for a short period before it transfers to the filter • 2. Filter • Identifies the message’s physical characteristics (tone, pitch, speed, accent, etc.) • 3. Detector • Info is processed to determine meaning • 4. Short-term memory • What comes out of detector goes to memory system where it can be used immediately or stored in long-term memory

Another Way of Thinking About It: • Also known as a “bottleneck theory”

Evidence Against the Bottleneck Model • The cocktail party effect (hearing something else across the room) • Errors in shadowing (Treisman, 1960)

Replication • The Dichotic listening experiment was repeated in 1960 by Anne Treisman • She found that even the message we’re filtering out is being processed on some level • Attended ear hears: “I saw the girl…song was wishing” • Unattended ear hears: “me that bird…jumping in the street” • Might put together: “I saw the girl jumping in the street”

Triesman’s Model • Similar to Broadbent, but instead of our minds filtering out the physical sound of message for us to focus on it, • Triesman said meaning and language also came into play when our mind was choosing what to focus on…especially when the two voices sound alike (both female or high pitched)

Treisman (cont.) • Message we decide to listen to is filtered by sound and meaning, and our minds focus on it…but • The attended message is just “louder” than the other…the other is still there in our subconscious like a whisper (not literally…think cocktail party again)

Treisman (cont.) • Finally, she said we have a Dictionary Unit • Contains stored words • Different words have different levels of activation • Your name = low threshold (takes little for us to turn our attention to) • Unimportant words to you = high threshold (takes a lot for you to notice them across the room)

TREISMAN’S MODEL OF SELECTIVE ATTENTION Attended Message Memo r y Attenuator Physical sound, language, and meaning Messages Dictionary Unit Unattended Message

Change Blindness • We can quickly take in whole scenes, but we often miss smaller details • This is especially true with changes in the big picture • (think about the changing pictures and basketball counting) http://www.youtube.com/watch?v=38XO7ac9eSs&feature=player_embedded

Automatic Processing • Processing that happens without us meaning to • Uses few Cognitive resources • Can help us do two things at once • Example of how an automatic process can interfere with a task…

Stroop Effect • http://faculty.washington.edu/chudler/java/ready.html • based on the work of John Ridley Stroop, Journal of Experiemental Psychology, 1935

Part 2 (minus the background  )