scholarly journals Neural Correlates of Encoding Within- and Across-domain Inter-item Associations

2011 ◽  
Vol 23 (9) ◽  
pp. 2533-2543 ◽  
Author(s):  
Heekyeong Park ◽  
Michael D. Rugg
Keyword(s):  
Medial Temporal Lobe ◽  
Inferior Frontal Gyrus ◽  
Temporal Cortex ◽  
Recognition Task ◽  
Neural Correlates ◽  
Memory Effects ◽  
Pair Type ◽  
General Role ◽  
The Difference ◽  
Cortical Regions

The neural correlates of the encoding of associations between pairs of words, pairs of pictures, and word–picture pairs were compared. The aims were to determine, first, whether the neural correlates of associative encoding vary according to study material and, second, whether encoding of across- versus within-material item pairs is associated with dissociable patterns of hippocampal and perirhinal activity, as predicted by the “domain dichotomy” hypothesis of medial temporal lobe function. While undergoing fMRI scanning, subjects (n = 24) were presented with the three classes of study pairs, judging which of the denoted objects fit into the other. Outside of the scanner, subjects then undertook an associative recognition task, discriminating between intact study pairs, rearranged pairs comprising items that had been presented on different study trials, and unstudied item pairs. The neural correlates of successful associative encoding—subsequent associative memory effects—were operationalized as the difference in activity between study pairs correctly judged intact versus pairs incorrectly judged rearranged on the subsequent memory test. Pair type–independent subsequent memory effects were evident in the left inferior frontal gyrus (IFG) and the hippocampus. Picture–picture pairs elicited material-selective effects in regions of fusiform cortex that were also activated to a greater extent on picture trials than on word trials, whereas word–word pairs elicited material-selective subsequent memory effects in left lateral temporal cortex. Contrary to the domain-dichotomy hypothesis, neither hippocampal nor perirhinal subsequent memory effects differed depending on whether they were elicited by within- versus across-material study pairs. It is proposed that the left IFG plays a domain-general role in associative encoding, that associative encoding can also be facilitated by enhanced processing in material-selective cortical regions, and that the hippocampus and perirhinal cortex contribute equally to the formation of inter-item associations, regardless of whether the items belong to the same or to different processing domains.

scholarly journals Decrements in Hippocampal Activity with Item Repetition during Continuous Recognition: An fMRI Study

2011 ◽  
Vol 23 (6) ◽  
pp. 1522-1532 ◽  
Author(s):  
Maki Suzuki ◽  
Jeffrey D. Johnson ◽  
Michael D. Rugg
Keyword(s):  
Temporal Lobe ◽  
Medial Temporal Lobe ◽  
Temporal Cortex ◽  
Recognition Task ◽  
Posterior Cingulate Cortex ◽  
Memory Strength ◽  
Hippocampal Activity ◽  
Cortical Regions ◽  
Different Response ◽  
The Right

fMRI (1.5 mm isotropic voxels) was employed to investigate the relationship between hippocampal activity and memory strength in a continuous recognition task. While being scanned, subjects were presented with colored photographs that each appeared on four occasions. The requirements were to make one response when an item was presented for the first or the third time and to make a different response when an item appeared for the second or the fourth time. Consistent with prior findings, items presented for the first time elicited greater hippocampal and parahippocampal activity than repeated items. The activity elicited by repeated items declined linearly as a function of number of presentations (“graded” new > old effects). No medial-temporal lobe regions could be identified where activity elicited by repeated items exceeded that for new items or where activity elicited by repeated items increased with number of presentations. These findings are inconsistent with the proposal that retrieval-related hippocampal activity is positively correlated with memory strength. We also identified graded new > old effects in several cortical regions outside the medial-temporal lobe, including the left retrosplenial/posterior cingulate cortex and the right lateral occipito-temporal cortex. By contrast, graded old > new effects were evident in bilateral mid-intraparietal sulcus and precuneus.

scholarly journals Performance of a Randomization Test for Single-Subject 15O-Water PET Activation Studies

1997 ◽  
Vol 17 (10) ◽  
pp. 1033-1039 ◽  
Author(s):  
Marco Halber ◽  
Karl Herholz ◽  
Klaus Wienhard ◽  
Gunter Pawlik ◽  
Wolf-Dieter Heiss
Keyword(s):  
Permutation Test ◽  
Inferior Frontal Gyrus ◽  
Test Procedure ◽  
Temporal Cortex ◽  
Randomization Test ◽  
Single Subject ◽  
Precentral Gyrus ◽  
Positron Emission ◽  
Filter Kernel ◽  
The Difference

We adapted and implemented a permutation test ( Holmes 1994 ) to single-subject positron emission tomography (PET) activation studies with multiple replications of conditions. That test determines the experimentwise α error as well as location and extent of focal activations in each individual. Its performance was assessed in five normal volunteers, using 15O-H2O-PET data acquired on a high-resolution scanner, with septa retracted (3D mode), during functional activation by repeating words versus resting (four replications each). Calculated α errors decreased and the size of activated tissue volumes (voxels with P ≤ 0.05) increased with increasing filter kernel size applied to the difference images. At a filter kernel of 12 mm Gaussian full width at half maximum, significant focal activations were seen bilaterally in superior temporal cortex, including Brodmann's areas 41 and 42, in all five subjects. Additional foci were detected in the precentral gyrus, left inferior frontal gyrus, supplementary motor area, and cerebellum of several subjects. The average CBF increase in activated voxels ranged from 17.6% to 28.7%. Activated volumes were smaller than those detected with a standard parametric test procedure. We conclude that the permutation test is a less sensitive procedure, having the advantage of not depending on unproven distributional assumptions, that detects strong activation foci in individual subjects with high reproducibility.

scholarly journals Episodic memory-related activation in schizophrenia: meta-analysis

2005 ◽  
Vol 187 (6) ◽  
pp. 500-509 ◽  
Author(s):  
Amélie M. Achim ◽  
Martin Lepage
Keyword(s):  
Episodic Memory ◽  
Temporal Lobe ◽  
Medial Temporal Lobe ◽  
Meta Analysis ◽  
Temporal Cortex ◽  
Neural Correlates ◽  
Brain Regions ◽  
Group Differences ◽  
Memory Encoding ◽  
The Brain

BackgroundNumerous studies have examined the neural correlates of episodic memory deficits in schizophrenia, yielding both consistencies and discrepancies in the reported patterns of results.AimsTo identify in schizophrenia the brain regions in which activity is consistently abnormal across imaging studies of memory.MethodData from 18 studies meeting the inclusion criteria were combined using a recently developed quantitative meta-analytic approach.ResultsRegions of consistent differential activation between groups were observed in the left inferior prefrontal cortex, medial temporal cortex bilaterally, left cerebellum, and in other prefrontal and temporal lobe regions. Subsequent analyses explored memory encoding and retrieval separately and identified between-group differences in specific prefrontal and medial temporal lobe regions.ConclusionsBeneath the apparent heterogeneity of published findings on schizophrenia and memory, a consistent and robust pattern of group differences is observed as a function of memory processes.

scholarly journals The Neural Correlates of Semantic Control Revisited

2020 ◽  
Author(s):  
Rebecca L. Jackson
Keyword(s):  
Semantic Network ◽  
Meta Analysis ◽  
Inferior Frontal Gyrus ◽  
Temporal Cortex ◽  
Neural Correlates ◽  
Middle Temporal Gyrus ◽  
Control Network ◽  
Temporal Region ◽  
List Type ◽  
Semantic Cognition

AbstractSemantic control, the ability to selectively access and manipulate meaningful information on the basis of context demands, is a critical component of semantic cognition. The precise neural correlates of semantic control are disputed, with particular debate surrounding parietal involvement, the spatial extent of the posterior temporal contribution and network lateralisation. Here semantic control is revisited, utilising improved analysis techniques and a decade of additional data to refine our understanding of the network. A meta-analysis of 876 peaks over 121 contrasts illuminated a left-focused network consisting of inferior frontal gyrus, posterior middle temporal gyrus, posterior inferior temporal gyrus and dorsomedial prefrontal cortex. This extended the temporal region implicated, and found no parietal involvement. Although left-lateralised overall, relative lateralisation varied across the implicated regions. Supporting analyses confirmed the multimodal nature of the semantic control network and situated it within the wider set of regions implicated in semantic cognition.Highlights➢A multimodal semantic control network was delineated with formal meta-analyses➢Semantic control recruits inferior and medial frontal and posterior temporal cortex➢A large extent of posterior temporal cortex was implicated and no parietal regions➢Semantic control is left-lateralised but regions show differential lateralisation➢The semantic control regions were situated in the context of the wider semantic network

scholarly journals Common and Unique Neural Activations in Autobiographical, Episodic, and Semantic Retrieval

2007 ◽  
Vol 19 (9) ◽  
pp. 1520-1534 ◽  
Author(s):  
Hana Burianova ◽  
Cheryl L. Grady
Keyword(s):  
Semantic Memory ◽  
Memory Retrieval ◽  
Medial Temporal Lobe ◽  
Declarative Memory ◽  
Inferior Frontal Gyrus ◽  
Imaging Study ◽  
Neural Correlates ◽  
Semantic Retrieval ◽  
Lingual Gyrus ◽  
Conscious Recollection

This study sought to explore the neural correlates that underlie autobiographical, episodic, and semantic memory. Autobiographical memory was defined as the conscious recollection of personally relevant events, episodic memory as the recall of stimuli presented in the laboratory, and semantic memory as the retrieval of factual information and general knowledge about the world. Our objective was to delineate common neural activations, reflecting a functional overlap, and unique neural activations, reflecting functional dissociation of these memory processes. We conducted an event-related functional magnetic resonance imaging study in which we utilized the same pictorial stimuli but manipulated retrieval demands to extract autobiographical, episodic, or semantic memories. The results show a functional overlap of the three types of memory retrieval in the inferior frontal gyrus, the middle frontal gyrus, the caudate nucleus, the thalamus, and the lingual gyrus. All memory conditions yielded activation of the left medial-temporal lobe; however, we found a functional dissociation within this region. The anterior and superior areas were active in episodic and semantic retrieval, whereas more posterior and inferior areas were active in autobiographical retrieval. Unique activations for each memory type were also delineated, including medial frontal increases for autobiographical, right middle frontal increases for episodic, and right inferior temporal increases for semantic retrieval. These findings suggest a common neural network underlying all declarative memory retrieval, as well as unique neural contributions reflecting the specific properties of retrieved memories.

scholarly journals Syntactic Complexity and Frequency in the Neurocognitive Language System

2017 ◽  
Vol 29 (9) ◽  
pp. 1605-1620 ◽  
Author(s):  
Yun-Hsuan Yang ◽  
William D. Marslen-Wilson ◽  
Mirjana Bozic
Keyword(s):  
Language Comprehension ◽  
Multivariate Analyses ◽  
Inferior Frontal Gyrus ◽  
Temporal Cortex ◽  
Frequency Effect ◽  
Syntactic Complexity ◽  
Left Inferior Frontal Gyrus ◽  
Fmri Study ◽  
Key Factor ◽  
Frequent Items

Prominent neurobiological models of language follow the widely accepted assumption that language comprehension requires two principal mechanisms: a lexicon storing the sound-to-meaning mapping of words, primarily involving bilateral temporal regions, and a combinatorial processor for syntactically structured items, such as phrases and sentences, localized in a left-lateralized network linking left inferior frontal gyrus (LIFG) and posterior temporal areas. However, recent research showing that the processing of simple phrasal sequences may engage only bilateral temporal areas, together with the claims of distributional approaches to grammar, raise the question of whether frequent phrases are stored alongside individual words in temporal areas. In this fMRI study, we varied the frequency of words and of short and long phrases in English. If frequent phrases are indeed stored, then only less frequent items should generate selective left frontotemporal activation, because memory traces for such items would be weaker or not available in temporal cortex. Complementary univariate and multivariate analyses revealed that, overall, simple words (verbs) and long phrases engaged LIFG and temporal areas, whereas short phrases engaged bilateral temporal areas, suggesting that syntactic complexity is a key factor for LIFG activation. Although we found a robust frequency effect for words in temporal areas, no frequency effects were found for the two phrasal conditions. These findings support the conclusion that long and short phrases are analyzed, respectively, in the left frontal network and in a bilateral temporal network but are not retrieved from memory in the same way as simple words during spoken language comprehension.

scholarly journals Sex differences in neural and behavioral signatures of cooperation revealed by fNIRS hyperscanning

2016 ◽  
Vol 6 (1) ◽  
Author(s):  
Joseph M. Baker ◽  
Ning Liu ◽  
Xu Cui ◽  
Pascal Vrticka ◽  
Manish Saggar ◽  
...  
Keyword(s):  
Sex Differences ◽  
Temporal Cortex ◽  
Neural Correlates ◽  
Behavioral Signatures ◽  
Computer Based ◽  
Males And Females ◽  
Brain And Behavior ◽  
The Right ◽  
And Behavior ◽  
The Brain

Abstract Researchers from multiple fields have sought to understand how sex moderates human social behavior. While over 50 years of research has revealed differences in cooperation behavior of males and females, the underlying neural correlates of these sex differences have not been explained. A missing and fundamental element of this puzzle is an understanding of how the sex composition of an interacting dyad influences the brain and behavior during cooperation. Using fNIRS-based hyperscanning in 111 same- and mixed-sex dyads, we identified significant behavioral and neural sex-related differences in association with a computer-based cooperation task. Dyads containing at least one male demonstrated significantly higher behavioral performance than female/female dyads. Individual males and females showed significant activation in the right frontopolar and right inferior prefrontal cortices, although this activation was greater in females compared to males. Female/female dyad’s exhibited significant inter-brain coherence within the right temporal cortex, while significant coherence in male/male dyads occurred in the right inferior prefrontal cortex. Significant coherence was not observed in mixed-sex dyads. Finally, for same-sex dyads only, task-related inter-brain coherence was positively correlated with cooperation task performance. Our results highlight multiple important and previously undetected influences of sex on concurrent neural and behavioral signatures of cooperation.

Neural correlates of long-term associative memory in human temporal cortex

2009 ◽  
Vol 65 ◽  
pp. S236
Author(s):  
Seiki Konishi ◽  
Ken-ichiro Yamashita ◽  
Satoshi Hirose ◽  
Akira Kunimatsu ◽  
Shigeki Aoki ◽  
...  
Keyword(s):  
Associative Memory ◽  
Temporal Cortex ◽  
Neural Correlates

Modulation of the Visual Word Retrieval System in Writing: A Functional MRI Study on the Japanese Orthographies

2002 ◽  
Vol 14 (1) ◽  
pp. 104-115 ◽  
Author(s):  
Kimihiro Nakamura ◽  
Manabu Honda ◽  
Shigeru Hirano ◽  
Tatsuhide Oga ◽  
Nobukatsu Sawamoto ◽  
...  
Keyword(s):  
Retrieval System ◽  
Temporal Cortex ◽  
Visual Word ◽  
Word Retrieval ◽  
Anterior Cingulate ◽  
Input Stimulus ◽  
Semantic Judgment ◽  
Cortical Regions ◽  
Mri Study ◽  
Mental Recall

We used functional magnetic resonance imaging (fMRI) to examine whether the act of writing involves different neuro-psychological mechanisms between the two script systems of the Japanese language: kanji (ideogram) and kana (phonogram). The main experiments employed a 2 × 2 factorial design that comprised writing-to-dictation and visual mental recall for kanji and kana. For both scripts, the actual writing produced a widespread fronto-parietal activation in the left hemisphere. Especially, writing of kanji activated the left posteroinferior temporal cortex (lPITC), whereas that of kana also yielded a trend of activation in the same area. Mental recall for both scripts activated similarly the left parieto-temporal regions including the lPITC. The writing versus mental recall comparison revealed greater activations in the left sensorimotor areas and right cerebellum. The kanji versus kana comparison showed increased responses in the left prefrontal and anterior cingulate areas. Especially, the lPITC showed a significant task-by-script interaction. Two additional control tasks, repetition (REP) and semantic judgment (SJ), activated the bilateral perisylvian areas, but enhanced the lPITC response only weakly. These results suggest that writing of the ideographic and phonographic scripts, although using the largely same cortical regions, each modulates the visual word-retrieval system according to their graphic features. Furthermore, comparisons with two additional tasks indicate that the activity of the lPITC increases especially in expressive language operations regardless of sensory modalities of the input stimulus.

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