Where numbers meet words: A common ventral network for semantic classification

Abstract

Recent research has shown that both language and number processing are clear examples of distributed and connected processing in the human brain, emphasizing the importance of white matter connections between the associated cortex sites. Against this background we hypothesized joint cognitive processes and functions in a cross-domain manner to be reflected by the involvement of specific white matter tracts. Therefore, we evaluated white matter connectivity for the specific cognitive process of semantic classification, which is an integral part of tasks commonly employed to investigate the neural correlates of language and number processing. In line with our expectations, fiber tracking results clearly indicated a common ventral network for semantic classification for the domains of language and number processing. Thereby, the present data are hard to reconcile with a localizationalist view on processing characteristics of the human brain, but strongly suggest that white matter connectivity should be considered when investigating the neural underpinnings of human cognition.

Unique Mapping of Structural and Functional Connectivity on Cognition

“…The PMAT fluid intelligence measures were particularly dominant, with higher rsFC correlating with higher PMAT accuracy and reaction times, so that subjects with higher rsFC were more accurate, but slower. We note that for both SC and FC, the PMAT measures were expressed in the second LVs, which is consistent with previous findings of a fluid intelligence-connectome link (Finn et al, 2015;Hearne et al, 2016;Smith, 2016;Ferguson et al, 2017).…”

“…Two LVs for SC and FC, respectively, each expressed a distinct and unique set of brain connections. This is in line with the view that distinct sets of connections are required to support cognition, implying more specialized connectivity (Rosenberg et al, 2013) rather than a global cognitive factor encompassed in a single set of connections (Malpas et al, 2016;Smith, 2016). We showed that while brain patterns that expressed cognitive variability did not overlap in SC and FC, the behavioral patterns did.…”

“…The corticostriatal-thalamic cognitive control loop also includes the brainstem (Peters et al, 2016), which exhibited cognition-related connectivity with the caudate in LV2. Moreover, the striatum (putamen and caudate) is specifically involved in learning, storing, and processing memories (Packard and Knowlton, 2002), and higher WM performance has been tied to higher connectivity between the cingulo-opercular network and the putamen rsFC (Tu et al, 2012). In LV1, the only subcortical region that had negative rsFC associations with cognition was the L hippocampus, which is consistent with prior work (Salami et al, 2014).…”

Unique Mapping of Structural and Functional Connectivity on Cognition

“…The PMAT fluid intelligence measures were particularly dominant, with higher rsFC correlating with higher PMAT accuracy and reaction times, so that subjects with higher rsFC were more accurate, but slower. We note that for both SC and FC, the PMAT measures were expressed in the second LVs, which is consistent with previous findings of a fluid intelligence-connectome link (Finn et al, 2015;Hearne et al, 2016;Smith, 2016;Ferguson et al, 2017).…”

“…Two LVs for SC and FC, respectively, each expressed a distinct and unique set of brain connections. This is in line with the view that distinct sets of connections are required to support cognition, implying more specialized connectivity (Rosenberg et al, 2013) rather than a global cognitive factor encompassed in a single set of connections (Malpas et al, 2016;Smith, 2016). We showed that while brain patterns that expressed cognitive variability did not overlap in SC and FC, the behavioral patterns did.…”

“…The corticostriatal-thalamic cognitive control loop also includes the brainstem (Peters et al, 2016), which exhibited cognition-related connectivity with the caudate in LV2. Moreover, the striatum (putamen and caudate) is specifically involved in learning, storing, and processing memories (Packard and Knowlton, 2002), and higher WM performance has been tied to higher connectivity between the cingulo-opercular network and the putamen rsFC (Tu et al, 2012). In LV1, the only subcortical region that had negative rsFC associations with cognition was the L hippocampus, which is consistent with prior work (Salami et al, 2014).…”

Neurocognitive Foundations of Child and Adult Number Processing : Neural Correlates and Functional Circuits Across Typical Development

“…This pattern may reflect the maturation of a ventral frontal-temporal-parietal network (cf. Brauer et al, 2013) that has previously been argued to support both numerical and linguistic semantic classification abilities (Willmes et al, 2014). Consequentially, this uniquely adult recruitment of perisylvian language network nodes calls for a child-specific conception of the triple code model's verbal code and further research into the neurocognitive mechanisms required for verbal number processing in children.…”

Differing Connectivity of Exner’s Area for Numbers and Letters

“…Our results corroborate the conclusion of Jung et al ( 2015 ) that the dissociation between handwriting of numbers vs. letters is due to differing connectivity of Exner’s area with cortex sites subserving number and language processing. These data indicate that domain-specificity in the human brain may evolve from the specific combination of activated cortex areas and their interconnections (see also Willmes et al, 2014 ). In particular, the present study indicates how informative the investigation of specific white matter connectivity can be when investigating the neural underpinnings of impaired or unimpaired human cognition.…”

Unique Mapping of Structural and Functional Connectivity on Cognition

“…The PMAT fluid intelligence measures were particularly dominant, with higher rsFC correlating with higher PMAT accuracy and reaction times, so that subjects with higher rsFC were more accurate, but slower. We note that for both SC and FC, the PMAT measures were expressed in the second LVs, which is consistent with previous findings of a fluid intelligence-connectome link (Finn et al, 2015;Hearne et al, 2016;Smith, 2016;Ferguson et al, 2017).…”

“…Two LVs for SC and FC, respectively, each expressed a distinct and unique set of brain connections. This is in line with the view that distinct sets of connections are required to support cognition, implying more specialized connectivity (Rosenberg et al, 2013) rather than a global cognitive factor encompassed in a single set of connections (Malpas et al, 2016;Smith, 2016). We showed that while brain patterns that expressed cognitive variability did not overlap in SC and FC, the behavioral patterns did.…”

“…The corticostriatal-thalamic cognitive control loop also includes the brainstem (Peters et al, 2016), which exhibited cognition-related connectivity with the caudate in LV2. Moreover, the striatum (putamen and caudate) is specifically involved in learning, storing, and processing memories (Packard and Knowlton, 2002), and higher WM performance has been tied to higher connectivity between the cingulo-opercular network and the putamen rsFC (Tu et al, 2012). In LV1, the only subcortical region that had negative rsFC associations with cognition was the L hippocampus, which is consistent with prior work (Salami et al, 2014).…”

Neurocognitive Foundations of Child and Adult Number Processing : Neural Correlates and Functional Circuits Across Typical Development

“…This pattern may reflect the maturation of a ventral frontal-temporal-parietal network (cf. Brauer et al, 2013) that has previously been argued to support both numerical and linguistic semantic classification abilities (Willmes et al, 2014). Consequentially, this uniquely adult recruitment of perisylvian language network nodes calls for a child-specific conception of the triple code model's verbal code and further research into the neurocognitive mechanisms required for verbal number processing in children.…”

Differing Connectivity of Exner’s Area for Numbers and Letters

“…Our results corroborate the conclusion of Jung et al ( 2015 ) that the dissociation between handwriting of numbers vs. letters is due to differing connectivity of Exner’s area with cortex sites subserving number and language processing. These data indicate that domain-specificity in the human brain may evolve from the specific combination of activated cortex areas and their interconnections (see also Willmes et al, 2014 ). In particular, the present study indicates how informative the investigation of specific white matter connectivity can be when investigating the neural underpinnings of impaired or unimpaired human cognition.…”

Unique Mapping of Structural and Functional Connectivity on Cognition

“…The PMAT fluid intelligence measures were particularly dominant, with higher rsFC correlating with higher PMAT accuracy and reaction times, so that subjects with higher rsFC were more accurate, but slower. We note that for both SC and FC, the PMAT measures were expressed in the second LVs, which is consistent with previous findings of a fluid intelligence-connectome link (Finn et al, 2015;Hearne et al, 2016;Smith, 2016;Ferguson et al, 2017).…”

“…Two LVs for SC and FC, respectively, each expressed a distinct and unique set of brain connections. This is in line with the view that distinct sets of connections are required to support cognition, implying more specialized connectivity (Rosenberg et al, 2013) rather than a global cognitive factor encompassed in a single set of connections (Malpas et al, 2016;Smith, 2016). We showed that while brain patterns that expressed cognitive variability did not overlap in SC and FC, the behavioral patterns did.…”

“…The corticostriatal-thalamic cognitive control loop also includes the brainstem (Peters et al, 2016), which exhibited cognition-related connectivity with the caudate in LV2. Moreover, the striatum (putamen and caudate) is specifically involved in learning, storing, and processing memories (Packard and Knowlton, 2002), and higher WM performance has been tied to higher connectivity between the cingulo-opercular network and the putamen rsFC (Tu et al, 2012). In LV1, the only subcortical region that had negative rsFC associations with cognition was the L hippocampus, which is consistent with prior work (Salami et al, 2014).…”

Neurocognitive Foundations of Child and Adult Number Processing : Neural Correlates and Functional Circuits Across Typical Development

“…This pattern may reflect the maturation of a ventral frontal-temporal-parietal network (cf. Brauer et al, 2013) that has previously been argued to support both numerical and linguistic semantic classification abilities (Willmes et al, 2014). Consequentially, this uniquely adult recruitment of perisylvian language network nodes calls for a child-specific conception of the triple code model's verbal code and further research into the neurocognitive mechanisms required for verbal number processing in children.…”

Differing Connectivity of Exner’s Area for Numbers and Letters

“…Our results corroborate the conclusion of Jung et al ( 2015 ) that the dissociation between handwriting of numbers vs. letters is due to differing connectivity of Exner’s area with cortex sites subserving number and language processing. These data indicate that domain-specificity in the human brain may evolve from the specific combination of activated cortex areas and their interconnections (see also Willmes et al, 2014 ). In particular, the present study indicates how informative the investigation of specific white matter connectivity can be when investigating the neural underpinnings of impaired or unimpaired human cognition.…”