The Influence of Multiple Primes on Bottom-Up and Top-Down Regulation during Meaning Retrieval: Evidence for 2 Distinct Neural Networks

TY - JOUR

T1 - The Influence of Multiple Primes on Bottom-Up and Top-Down Regulation during Meaning Retrieval: Evidence for 2 Distinct Neural Networks

AU - Whitney, Carin

AU - Grossman, Murray

AU - Kircher, Tilo T. J.

PY - 2009/11

Y1 - 2009/11

N2 - Meaning retrieval of a word can proceed fast and effortlessly or can be characterized by a controlled search for candidate lexical items and a subsequent selection process. In the current study, we facilitated meaning retrieval by increasing the number of words that were related to the final target word in a triplet (e.g., lion-stripes-tiger). To induce higher search and selection demands, we presented ambiguous words as targets (i.e., homonyms like ball) in half of the trials. Hereby, the dominant (game), low-frequent (dance), or both meanings of the homonym were primed. Participants performed a relatedness judgment during functional magnetic resonance imaging. Activation in a bilateral network (angular gyrus, rostromedial prefrontal cortex) increased linearly with multiple related primes, whereas the posterior left inferior prefrontal cortex (pLIPC) showed the reverse activation pattern for unambiguous trials. When homonyms served as targets, pLIPC responded strongest when both meanings or low-frequent concepts were addressed. Additional anterior left inferior prefrontal cortex activation was observed for the latter trials only. The data support an interaction between 2 distinct cerebral networks that can be linked to automatic bottom-up support and top-down control during meaning retrieval. They further imply a functional specialization of the LIPC along an anterior-posterior dimension.

AB - Meaning retrieval of a word can proceed fast and effortlessly or can be characterized by a controlled search for candidate lexical items and a subsequent selection process. In the current study, we facilitated meaning retrieval by increasing the number of words that were related to the final target word in a triplet (e.g., lion-stripes-tiger). To induce higher search and selection demands, we presented ambiguous words as targets (i.e., homonyms like ball) in half of the trials. Hereby, the dominant (game), low-frequent (dance), or both meanings of the homonym were primed. Participants performed a relatedness judgment during functional magnetic resonance imaging. Activation in a bilateral network (angular gyrus, rostromedial prefrontal cortex) increased linearly with multiple related primes, whereas the posterior left inferior prefrontal cortex (pLIPC) showed the reverse activation pattern for unambiguous trials. When homonyms served as targets, pLIPC responded strongest when both meanings or low-frequent concepts were addressed. Additional anterior left inferior prefrontal cortex activation was observed for the latter trials only. The data support an interaction between 2 distinct cerebral networks that can be linked to automatic bottom-up support and top-down control during meaning retrieval. They further imply a functional specialization of the LIPC along an anterior-posterior dimension.

KW - angular gyrus

KW - fMRI

KW - inferior frontal cortex

KW - selection

KW - semantic priming

KW - PREFRONTAL CORTEX AREA-10

KW - EVENT-RELATED FMRI

KW - RESONANCE-IMAGING EVIDENCE

KW - LEXICALLY AMBIGUOUS WORDS

KW - SENTENCE COMPREHENSION

KW - TIME-COURSE

KW - CYTOARCHITECTONIC MAPS

KW - CEREBRAL HEMISPHERES

KW - SELECTION MECHANISMS

KW - SEMANTIC IMPAIRMENT

UR - http://www.scopus.com/inward/record.url?scp=70349907741&partnerID=8YFLogxK

U2 - 10.1093/cercor/bhp007

DO - 10.1093/cercor/bhp007

M3 - Literature review

SN - 1047-3211

VL - 19

SP - 2548

EP - 2560

JO - Cerebral Cortex

JF - Cerebral Cortex

IS - 11

ER -