Source versus content memory in patients with a unilateral frontal cortex or a temporal lobe excision

Abstract Visual search is a fundamental human behavior, providing a gateway to understanding other sensory domains as well as the role of search in higher-order cognition. Search has been proposed to include two component processes: inefficient search (search) and efficient search (pop-out). According to extant research, these two processes map onto two separable neural systems located in the frontal and parietal association cortices. In this study, we use intracranial recordings from 23 participants to delineate the neural correlates of search and pop-out with an unprecedented combination of spatiotemporal resolution and coverage across cortical and subcortical structures. First, we demonstrate a role for the medial temporal lobe in visual search, on par with engagement in frontal and parietal association cortex. Second, we show a gradient of increasing engagement over anatomical space from dorsal to ventral lateral frontal cortex. Third, we confirm previous intracranial work demonstrating nearly complete overlap in neural engagement across cortical regions in search and pop-out. We further demonstrate pop-out selectivity, manifesting as activity increase in pop-out as compared to search, in a distributed set of sites including frontal cortex. This result is at odds with the view that pop-out is implemented in low-level visual cortex or parietal cortex alone. Finally, we affirm a central role for the right lateral frontal cortex in search.

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Ventrolateral and dorsomedial frontal cortex lesions impair mnemonic context retrieval

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2014.2555 ◽

2015 ◽

Vol 282 (1801) ◽

pp. 20142555 ◽

Cited By ~ 13

Author(s):

Catherine Chapados ◽

Michael Petrides

Keyword(s):

Prefrontal Cortex ◽

Recognition Memory ◽

Frontal Cortex ◽

Temporal Lobe ◽

Context Condition ◽

Multiple Contexts ◽

Dorsomedial Frontal Cortex ◽

Prefrontal Region ◽

The Stability ◽

The Right

The prefrontal cortex appears to contribute to the mnemonic retrieval of the context within which stimuli are experienced, but only under certain conditions that remain to be clarified. Patients with lesions to the frontal cortex, the temporal lobe and neurologically intact individuals were tested for context memory retrieval when verbal stimuli (words) had been experienced across multiple (unstable context condition) or unique (stable context condition) contexts; basic recognition memory of these words-in-contexts was also tested. Patients with lesions to the right ventrolateral prefrontal cortex (VLPFC) were impaired on context retrieval only when the words had been seen in multiple contexts, demonstrating that this prefrontal region is critical for active retrieval processing necessary to disambiguate memory items embedded across multiple contexts. Patients with lesions to the left dorsomedial prefrontal region were impaired on both context retrieval conditions, regardless of the stability of the stimulus-to-context associations. Conversely, prefrontal lesions sparing the ventrolateral and dorsomedial regions did not impair context retrieval. Only patients with temporal lobe excisions were impaired on basic recognition memory. The results demonstrate a basic contribution of the left dorsomedial frontal region to mnemonic context retrieval, with the VLPFC engaged, selectively, when contextual relations are unstable and require disambiguation.

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Evidence of glutamatergic dysfunction in orbital frontal cortex and left temporal lobe in schizophrenia

Schizophrenia Research ◽

10.1016/0920-9964(88)90094-1 ◽

1988 ◽

Vol 1 (2-3) ◽

pp. 142-143

Keyword(s):

Frontal Cortex ◽

Temporal Lobe ◽

Orbital Frontal Cortex ◽

Left Temporal Lobe

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Hemispheric Specialization in Human Dorsal Frontal Cortex and Medial Temporal Lobe for Verbal and Nonverbal Memory Encoding

Neuron ◽

10.1016/s0896-6273(00)80474-2 ◽

1998 ◽

Vol 20 (5) ◽

pp. 927-936 ◽

Cited By ~ 561

Author(s):

William M Kelley ◽

Francis M Miezin ◽

Kathleen B McDermott ◽

Randy L Buckner ◽

Marcus E Raichle ◽

...

Keyword(s):

Frontal Cortex ◽

Temporal Lobe ◽

Medial Temporal Lobe ◽

Hemispheric Specialization ◽

Memory Encoding ◽

Nonverbal Memory

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Frontal language areas do not emerge in the absence of temporal language areas: A case study of an individual born without a left temporal lobe

10.1101/2021.05.28.446230 ◽

2021 ◽

Author(s):

Greta Tuckute ◽

Alexander Paunov ◽

Hope Kean ◽

Hannah Small ◽

Zachary Mineroff ◽

...

Keyword(s):

Frontal Cortex ◽

Frontal Lobe ◽

Temporal Lobe ◽

Language Processing ◽

Right Hemisphere ◽

Left Temporal Lobe ◽

High Level ◽

Temporal Language ◽

Language Areas

High-level language processing is supported by a left-lateralized fronto-temporal brain network. How this network emerges ontogenetically remains debated. Given that frontal cortex in general exhibits protracted development, frontal language areas presumably emerge later and/or mature more slowly than temporal language areas. But are temporal areas necessary for the development of the language areas in the frontal lobe, or do frontal language areas instead emerge independently? We shed light on this question through a case study of an individual (EG) born without a left temporal lobe. We use fMRI methods that have been previously extensively validated for their ability to elicit robust language responses at the individual-subject level. As expected in cases of early left hemisphere (LH) damage, we find that EG has a fully functional language network in her right hemisphere (RH) and performs within the normal range on standardized language assessments. However, her RH frontal language areas have no corresponding LH homotopic areas: no reliable response to language is detected on the lateral surface of EG's left frontal lobe. However, another network implicated in high-level cognition - the domain-general multiple demand, MD, network - is robustly present in both right and left frontal lobes, suggesting that EG's left frontal cortex is capable of supporting non-linguistic cognitive functions. The existence of temporal language areas therefore appears to be a prerequisite for the emergence of the language areas in the frontal lobe.

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Intracranial recordings demonstrate medial temporal lobe engagement in visual search in humans

10.1101/2020.02.29.971341 ◽

2020 ◽

Author(s):

S. J. Katarina Slama ◽

Richard Jimenez ◽

Sujayam Saha ◽

David King-Stephens ◽

Kenneth D. Laxer ◽

...

Keyword(s):

Visual Search ◽

Frontal Cortex ◽

Temporal Lobe ◽

Medial Temporal Lobe ◽

Association Cortex ◽

Subcortical Structures ◽

Spatiotemporal Resolution ◽

Activity Increase ◽

Anatomical Space ◽

Intracranial Recordings

AbstractVisual search is a fundamental human behavior, which has been proposed to include two component processes: inefficient search (Search) and efficient search (Pop-out). According to extant research, these two processes map onto two separable neural systems located in the frontal and parietal association cortices. In the present study, we use intracranial recordings from 23 participants to delineate the neural correlates of Search and Pop-out with an unprecedented combination of spatiotemporal resolution and coverage across cortical and subcortical structures. First, we demonstrate a role for the medial temporal lobe in visual search, on par with engagement in frontal and parietal association cortex. Second, we show a gradient of increasing engagement over anatomical space from dorsal to ventral lateral frontal cortex. Third, we confirm previous work demonstrating nearly complete overlap in neural engagement across cortical regions in Search and Pop-out. We further demonstrate Pop-out selectivity manifesting as activity increase in Pop-out as compared to Search in a distributed set of sites including frontal cortex. This result is at odds with the view that Pop-out is implemented in low-level visual cortex or parietal cortex alone. Finally, we affirm a central role for the right lateral frontal cortex in Search.

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Lexical-semantic processing in the semantic priming paradigm in aphasic patients

Arquivos de Neuro-Psiquiatria ◽

10.1590/s0004-282x2012000900014 ◽

2012 ◽

Vol 70 (9) ◽

pp. 718-726 ◽

Cited By ~ 8

Author(s):

Jerusa Fumagalli de Salles ◽

Candice Steffen Holderbaum ◽

Maria Alice Mattos Pimenta Parente ◽

Letícia Lessa Mansur ◽

Ana Inès Ansaldo

Keyword(s):

Frontal Cortex ◽

Semantic Priming ◽

Temporal Lobe ◽

Semantic Processing ◽

Functional Neuroimaging ◽

International Literature ◽

Priming Effects ◽

Lexical Semantic ◽

Priming Paradigm ◽

Implicit And Explicit

There is evidence that the explicit lexical-semantic processing deficits which characterize aphasia may be observed in the absence of implicit semantic impairment. The aim of this article was to critically review the international literature on lexical-semantic processing in aphasia, as tested through the semantic priming paradigm. Specifically, this review focused on aphasia and lexical-semantic processing, the methodological strengths and weaknesses of the semantic paradigms used, and recent evidence from neuroimaging studies on lexical-semantic processing. Furthermore, evidence on dissociations between implicit and explicit lexical-semantic processing reported in the literature will be discussed and interpreted by referring to functional neuroimaging evidence from healthy populations. There is evidence that semantic priming effects can be found both in fluent and in non-fluent aphasias, and that these effects are related to an extensive network which includes the temporal lobe, the pre-frontal cortex, the left frontal gyrus, the left temporal gyrus and the cingulated cortex.

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