Recognizing the unknown: Motor-response execution reflects the availability of positive evidence during recognition

Area of Science:

• Cognitive Psychology
• Neuroscience
• Human Computer Interaction

Background:

• Recognition is fundamental to cognition, but the process of categorizing unknown stimuli is not fully understood.
• The influence of evidence certainty on motor response execution during stimulus recognition requires further investigation.

Purpose of the Study:

• To investigate how the presence versus absence of positive evidence affects motor-response execution during stimulus recognition.
• To differentiate the impact of stimulus word-likeness and evidence certainty on premotor and motor response components.

Main Methods:

• A visual lexical decision task was employed with five stimulus categories: high-frequency words, low-frequency words, letter-substitution pseudowords, pseudowords, and illegal letter strings.
• Stimulus categories varied along a word-likeness gradient.
• The effects of stimulus category on premotor and motor response times were analyzed separately.

Main Results:

• Premotor times (and reaction times) varied with word-likeness, with extreme categories (high-frequency words, illegal strings) yielding faster responses than ambiguous categories.
• Motor times, reflecting motor-response execution, were insensitive to word-likeness.
• Motor times were faster for stimuli with clear lexical status (words, illegal strings) compared to those without (pseudowords, substitution pseudowords).

Conclusions:

• Decisional dynamics differentially modulate premotor and motor response times during recognition.
• Motor-response execution is selectively influenced by the presence or absence of positive evidence, rather than general word-likeness.
• Memory-based recognition processes are differentiated by the availability of positive evidence, especially concerning action implementation.