A participant shadows (repeats aloud) one ear's audio stream while ignoring the other. Later they report hearing their name in the 'ignored' channel. Which model best explains this finding and how?
ABroadbent's filter theory — the filter allows personally relevant signals to pass before semantic processing
BTreisman's attenuation theory — the unattended channel is weakened but not blocked; high-threshold words like one's name break through
CLate selection theory — all channels are fully blocked after the filter, but name recognition is innate
DBroadbent's filter theory — physical channel properties (pitch of one's own name) allow it to bypass the filter
The cocktail party effect — noticing your name in the unattended channel — directly challenged Broadbent's early filter, which predicted complete pre-semantic blocking of unattended channels. Treisman's attenuation model handles it by proposing the unattended channel is attenuated (weakened) rather than blocked, and that words with high personal relevance have low thresholds for conscious access, allowing them to break through even attenuated signals.
Question 2 Multiple Choice
A researcher designs a demanding visual search task (high perceptual load) and a simple target detection task (low perceptual load). According to the perceptual load hypothesis, in which condition should irrelevant distractors produce more interference?
AHigh perceptual load — the demanding task forces processing of all stimuli including distractors
BLow perceptual load — spare processing capacity spills over to process distractors, producing interference
CBoth equally — distractor interference is independent of task demands
DHigh perceptual load — more cognitive resources mean more distractor processing
The perceptual load hypothesis proposes that when the attended task consumes most available perceptual capacity (high load), little capacity remains for distractors — selection is early. When the task is easy (low load), spare capacity automatically processes distractors — selection is late, and distractors interfere. This explains why simple tasks produce more distractor interference despite seeming less demanding.
Question 3 True / False
Broadbent's original filter theory proposed that the unattended channel is processed to a semantic level but blocked from reaching consciousness.
TTrue
FFalse
Answer: False
Broadbent proposed a pre-semantic bottleneck: the filter operates on physical features (location, pitch) *before* any semantic content is extracted, and the unattended channel is blocked entirely. It was Treisman's attenuation theory and later late-selection theories that introduced semantic processing of unattended material. If Broadbent were right, you could never notice your name in the ignored channel.
Question 4 True / False
Under high perceptual load, distractors are less likely to interfere with the attended task than under low perceptual load.
TTrue
FFalse
Answer: True
This is the central prediction of Lavie's perceptual load hypothesis. High load consumes available perceptual capacity, preventing distractors from being processed — producing early selection and low distractor interference. The counterintuitive implication is that making a task harder can reduce distraction, because there is no spare capacity to 'waste' on irrelevant information.
Question 5 Short Answer
Why is the debate between early and late selection theories ultimately a debate about the relationship between perception and consciousness?
Think about your answer, then reveal below.
Model answer: Early selection theories hold that meaning is extracted only from attended stimuli — unattended information is blocked before semantic processing occurs, so consciousness is tightly coupled to the filter's gate. Late selection theories hold that all stimuli are fully processed semantically before selection occurs — the filter determines what we respond to, not what we perceive. The two positions disagree about where unconscious perceptual registration ends and conscious awareness begins.
The filter's location is not merely a technical question about processing stages — it defines what 'attention' means. Early selection makes attention a perceptual gate that controls what gets recognized. Late selection makes it a post-perceptual gate that controls what gets acted on or consciously reported. This maps onto broader debates about whether perception can occur without awareness and how much of the world we unconsciously process at any moment.