Final answer:
Broadbent's early selection theory cannot explain the cocktail party effect because it suggests stimuli are filtered before being processed for meaning, which doesn't allow for the detection of personally relevant information in an unattended channel.
Step-by-step explanation:
The student's question is asking which theory cannot explain the cocktail party effect, where an individual can focus auditory attention on a particular stimulus while filtering out a range of other stimuli. The theories mentioned are related to attention, processing, and perception. Broadbent's early selection theory is the one that cannot adequately explain the cocktail party effect as it suggests that stimuli are filtered at an early stage before being processed for meaning, which seems to counter the ability of people to detect personally relevant information like their name in an unattended channel.
Review of Given Options:
Filter theory - A general term that could refer to a range of theories regarding how we filter information from our environment, some of which could potentially explain the cocktail party effect.
Broadbent's early selection theory - Proposes that information is selected based on physical characteristics and other stimuli are filtered out early in the processing stage, which does not account for the detection of unattended but relevant information.
Treisman's attenuation theory - Suggests a more flexible approach to filtering, where unattended information is not completely blocked but attenuated or turned down, which could explain the detection of important unattended information like one's own name.
Kahneman's capacity model - Emphasizes the allocation of limited cognitive resources based on demand and task difficulty, it suggests that attention can be shifted based on the importance of the stimuli, which could also potentially explain the cocktail party effect.