Self-prioritization in motor responses

Thesis

In psychology, self-representation is widely held to guide our cognition and action. Self-relevant stimuli typically enhance our attention, perception, memory, and decision-making. A shape-label matching paradigm provides a standard method for investigating the self-advantage. However, the evidence suggests that self-prioritization (self-bias) in the matching task may be distinct from higher-level self-referential processing. To better understand the operation of this subcomponent of self, this thesis took a broad approach and asked: what are contextual constraints on the emergence and extent of self-bias in manual motor responses? Self-bias was examined with unisensory and multisensory stimuli and manipulations of stimulus factors and task-design, for the first time in a multisensory detection motor paradigm, in the initiation and execution of arm-movements, and in the relationship between self-bias and subjective perceptions of empathy and perceived closeness to others.

This thesis demonstrates that: (1) stimulus and label modality and task-design can modulate self-bias; (2) self-associations did not produce similar motor speed gains in simple detection motor responses, suggesting that self-bias in motor responses to unisensory and multisensory stimuli depends on explicit self–other evaluations; (3) self-bias can influence non-ballistic visual-feedback-driven arm-movements, ballistic arm-movements without visual feedback, and arm-movements directed ‘toward’ and ‘away’ from the stimuli; in other words, self-bias modulates ballistic arm-movements using proprioceptive, kinaesthetic, and tactile information (and potentially visual imagery), but not relevant exogenous visual input; (4) self-bias can influence both the initiation and execution of arm-movements; highlighting a modulation at multiple stages; (5) empathy and perceived closeness can predict self-bias and friend-bias, suggesting that the biases in manual motor responses are influenced by consciously-accessible representations of the interrelations between others and the self.

The wider implications of these findings are discussed in relation to neurodevelopmental disorders and relevance for future translational research. Taken together, these findings present a novel overview of self-bias in manual motor responses.

Authors: Desebrock, C

• DOI: 10.5287/ora-kzaymdge2
• Type of award: DPhil
• Level of award: Doctoral
• Awarding institution: University of Oxford
• Language: English
• Keywords: Movement time; Self-relevance; Self-Prioritization Effect; Arm-movement responses; Personal distance; Manual motor responses; Empathy; Self-prioritization; Multisensory processing; Self-referential processing
• Subjects: Cognitive psychology; Cognitive neuroscience; Social sciences and psychology; Psychophysics; Social psychology