scholarly journals Subliminal Convergence of Kanji and Kana Words: Further Evidence for Functional Parcellation of the Posterior Temporal Cortex in Visual Word Perception

2005 ◽  
Vol 17 (6) ◽  
pp. 954-968 ◽  
Author(s):  
Kimihiro Nakamura ◽  
Stanislas Dehaene ◽  
Antoinette Jobert ◽  
Denis Le Bihan ◽  
Sid Kouider
Keyword(s):  
Temporal Cortex ◽  
Visual Word ◽  
Inferior Temporal Cortex ◽  
Temporal Region ◽  
Writing Systems ◽  
Semantic Level ◽  
Visual Words ◽  
Processing Level ◽  
Word Repetition ◽  
Repetition Suppression

Recent evidence has suggested that the human occipito-temporal region comprises several subregions, each sensitive to a distinct processing level of visual words. To further explore the functional architecture of visual word recognition, we employed a subliminal priming method with functional magnetic resonance imaging (fMRI) during semantic judgments of words presented in two different Japanese scripts, Kanji and Kana. Each target word was preceded by a subliminal presentation of either the same or a different word, and in the same or a different script. Behaviorally, word repetition produced significant priming regardless of whether the words were presented in the same or different script. At the neural level, this cross-script priming was associated with repetition suppression in the left inferior temporal cortex anterior and dorsal to the visual word form area hypothesized for alphabetical writing systems, suggesting that cross-script convergence occurred at a semantic level. fMRI also evidenced a shared visual occipito-temporal activation for words in the two scripts, with slightly more mesial and right-predominant activation for Kanji and with greater occipital activation for Kana. These results thus allow us to separate script-specific and script-independent regions in the posterior temporal lobe, while demonstrating that both can be activated subliminally.

scholarly journals Within and between hemifields generalization of repetition suppression in inferior temporal cortex.

2020 ◽  
Author(s):  
Francesco Fabbrini ◽  
Rufin Vogels
Keyword(s):  
Test Stimulus ◽  
Common Property ◽  
Temporal Cortex ◽  
Receptive Fields ◽  
Selective Adaptation ◽  
Inferior Temporal Cortex ◽  
Repetition Suppression ◽  
Repetition Trial ◽  
End Stage ◽  
Spatial Locations

The decrease in response with stimulus repetition is a common property observed in many sensory brain areas. This repetition suppression (RS) is ubiquitous in neurons of macaque inferior temporal (IT) cortex, the end-stage of the ventral visual pathway. The neural mechanisms of RS in IT are still unclear, and one possibility is that it is inherited from areas upstream to IT that show also RS. Since neurons in IT have larger receptive fields compared to earlier visual areas, we examined the inheritance hypothesis by presenting adapter and test stimuli at widely different spatial locations along both vertical and horizontal meridians, and across hemifields. RS was present for distances between adapter and test stimuli up to 22°, and when the two stimuli were presented in different hemifields. Also, we examined the position tolerance of the stimulus selectivity of adaptation by comparing the responses to a test stimulus following the same (repetition trial) or a different adapter (alternation trial) at a different position than the test stimulus. Stimulus-selective adaptation was still present and consistently stronger in the later phase of the response for distances up to 18°. Finally, we observed stimulus-selective adaptation in repetition trials even without a measurable excitatory response to the adapter stimulus. To accommodate these and previous data, we propose that at least part of the stimulus-selective adaptation in IT is based on short-term plasticity mechanisms within IT and/or reflects top-down activity from areas downstream to IT.

scholarly journals Left-lateralized N170 Effects of Visual Expertise in Reading: Evidence from Japanese Syllabic and Logographic Scripts

2008 ◽  
Vol 20 (10) ◽  
pp. 1878-1891 ◽  
Author(s):  
Urs Maurer ◽  
Jason D. Zevin ◽  
Bruce D. McCandliss
Keyword(s):  
Event Related Potential ◽  
Visual Word ◽  
Writing Systems ◽  
Visual Expertise ◽  
Native Japanese Speakers ◽  
Visual Words ◽  
Repetition Detection ◽  
N170 Component ◽  
Word Forms ◽  
Series Of Experiments

The N170 component of the event-related potential (ERP) reflects experience-dependent neural changes in several forms of visual expertise, including expertise for visual words. Readers skilled in writing systems that link characters to phonemes (i.e., alphabetic writing) typically produce a left-lateralized N170 to visual word forms. This study examined the N170 in three Japanese scripts that link characters to larger phonological units. Participants were monolingual English speakers (EL1) and native Japanese speakers (JL1) who were also proficient in English. ERPs were collected using a 129-channel array, as participants performed a series of experiments viewing words or novel control stimuli in a repetition detection task. The N170 was strongly left-lateralized for all three Japanese scripts (including logographic Kanji characters) in JL1 participants, but bilateral in EL1 participants viewing these same stimuli. This demonstrates that left-lateralization of the N170 is dependent on specific reading expertise and is not limited to alphabetic scripts. Additional contrasts within the moraic Katakana script revealed equivalent N170 responses in JL1 speakers for familiar Katakana words and for Kanji words transcribed into novel Katakana words, suggesting that the N170 expertise effect is driven by script familiarity rather than familiarity with particular visual word forms. Finally, for English words and novel symbol string stimuli, both EL1 and JL1 subjects produced equivalent responses for the novel symbols, and more left-lateralized N170 responses for the English words, indicating that such effects are not limited to the first language. Taken together, these cross-linguistic results suggest that similar neural processes underlie visual expertise for print in very different writing systems.

scholarly journals Intact reading ability in spite of a spatially distributed visual word form 'area' in an individual born without the left superior temporal lobe

2021 ◽  
Author(s):  
Jin Li ◽  
Evelina Fedorenko ◽  
Zeynep M. Saygin
Keyword(s):  
Temporal Lobe ◽  
Reading Ability ◽  
Temporal Cortex ◽  
Past Research ◽  
Visual Word ◽  
Word Form ◽  
Visual Words ◽  
Visual Word Form Area ◽  
Ventral Temporal Cortex ◽  
Language Network

The visual word form area (VWFA) is an experience-dependent brain region in the left ventral temporal cortex of literate adults that responds selectively to visual words. Why does it emerge in this stereotyped location? Past research has shown that the VWFA is preferentially connected to the left-lateralized frontotemporal language network. However, it remains unclear whether the presence of a typical language network and its connections with ventral temporal cortex (VTC) are critical for the VWFA's emergence, and whether alternative functional architectures may support reading ability. We explored these questions in an individual (EG) born without the left superior temporal lobe but exhibiting normal reading ability. Using fMRI, we recorded brain activation to visual words, objects, faces, and scrambled words in EG and neurotypical controls. We did not observe word selectivity either in EG's right homotope of the VWFA (rVWFA)—the most expected location given that EG's language network is right-lateralized—or in her spared left VWFA (lVWFA), in the presence of typical face selectivity in both the right and left fusiform face area (rFFA, lFFA). Interestingly, multivariate pattern analyses revealed voxels in EG's rVWFA and lVWFA that showed 1) higher within- than between- category correlations for words (e.g., Words-Words>Words-Faces), and 2) higher within-category correlations for words than other categories (e.g., Words-Words>Faces-Faces). These results suggest that a typical left-hemisphere language network may be necessary for the emergence of focal word selectivity within ventral temporal cortex, and that orthographic processing may depend on a distributed neural code, which appears capable of supporting reading ability.

scholarly journals Repetition suppression for visual actions in the macaque superior temporal sulcus

2016 ◽  
Vol 115 (3) ◽  
pp. 1324-1337 ◽  
Author(s):  
Pradeep Kuravi ◽  
Vittorio Caggiano ◽  
Martin Giese ◽  
Rufin Vogels
Keyword(s):  
Mirror Neurons ◽  
Temporal Cortex ◽  
Event Related Potentials ◽  
Superior Temporal Sulcus ◽  
Inferior Temporal Cortex ◽  
Repetition Suppression ◽  
Related Potentials ◽  
Hand Action ◽  
Spiking Activity ◽  
Adaptation Effects

In many brain areas, repetition of a stimulus usually weakens the neural response. This “adaptation” or repetition suppression effect has been observed with mass potential measures such as event-related potentials (ERPs), in fMRI BOLD responses, and locally with local field potentials (LFPs) and spiking activity. Recently, it has been reported that macaque F5 mirror neurons do not show repetition suppression of their spiking activity for single repetitions of hand actions, which disagrees with human fMRI adaptation studies. This finding also contrasts with numerous studies showing repetition suppression in macaque inferior temporal cortex, including the rostral superior temporal sulcus (STS). Since the latter studies employed static stimuli, we assessed here whether the use of dynamic action stimuli abolishes repetition suppression in the awake macaque STS. To assess adaptation effects in the STS, we employed the same hand action movies as used when examining adaptation in F5. The upper bank STS neurons showed repetition suppression during the approaching phase of the hand action, which corresponded to the phase of the action for which these neurons responded overall the strongest. The repetition suppression was present for the spiking activity measured in independent single-unit and multiunit recordings as well as for the LFP power at frequencies > 50 Hz. Together with previous data in F5, these findings suggest that adaptation effects differ between F5 mirror neurons and the STS neurons.

scholarly journals On the Functional Neuroanatomy of Visual Word Processing: Effects of Case and Letter Deviance

2009 ◽  
Vol 21 (2) ◽  
pp. 222-229 ◽  
Author(s):  
Martin Kronbichler ◽  
Johannes Klackl ◽  
Fabio Richlan ◽  
Matthias Schurz ◽  
Wolfgang Staffen ◽  
...  
Keyword(s):  
Word Processing ◽  
Imaging Study ◽  
Visual Word ◽  
Temporal Region ◽  
Functional Neuroanatomy ◽  
Visual Words ◽  
Visual Word Form Area ◽  
Left Posterior ◽  
Processing Effects ◽  
Letter Processing

This functional magnetic resonance imaging study contrasted case-deviant and letter-deviant forms with familiar forms of the same phonological words (e.g., TaXi and Taksi vs. Taxi) and found that both types of deviance led to increased activation in a left occipito-temporal region, corresponding to the visual word form area (VWFA). The sensitivity of the VWFA to both types of deviance may suggest that this region represents well-known visual words not only as sequences of abstract letter identities but also includes information on the typical case-format pattern of visual words. Case-deviant items, in addition, led to increased activation in a right occipito-temporal region and in a left occipital and a left posterior occipito-temporal region, which may reflect increased demands on letter processing posed by the case-deviant forms.

scholarly journals Probing the Mechanisms of Repetition Suppression in Inferior Temporal Cortex with Optogenetics

2019 ◽  
Vol 29 (12) ◽  
pp. 1988-1998.e4 ◽  
Author(s):  
Francesco Fabbrini ◽  
Chris Van den Haute ◽  
Marina De Vitis ◽  
Veerle Baekelandt ◽  
Wim Vanduffel ◽  
...  
Keyword(s):  
Temporal Cortex ◽  
Inferior Temporal Cortex ◽  
Repetition Suppression

scholarly journals Name Calling in the Temporal Lobe

2008 ◽  
Vol 8 (6) ◽  
pp. 156-158
Author(s):  
Warren T. Blume ◽  
Brent Hayman-Abello
Keyword(s):  
Temporal Lobe ◽  
Posterior Distribution ◽  
Hippocampal Sclerosis ◽  
Temporal Cortex ◽  
Cortical Reorganization ◽  
Inferior Temporal Cortex ◽  
Temporal Region ◽  
Lexical Information ◽  
Temporal Lobe Resection

Evidence for Cortical Reorganization of Language in Patients with Hippocampal Sclerosis. Hamberger MJ, Seidel WT, Goodman RR, Williams A, Perrine K, Devinsky O, McKhann GM 2nd. Brain 2007;130(Pt 11):2942–2950. Naming is mediated by perisylvian cortex in the left (language-dominant) hemisphere, and thus, left anterior temporal lobe resection for pharmacologically intractable temporal lobe epilepsy (TLE) carries risk for post-operative naming decline. Interestingly, this risk is lower in patients with hippocampal sclerosis (HS) relative to those without HS (non-HS). Although the hippocampus has traditionally been considered a critical structure for memory, without contribution to naming, this pattern might implicate direct hippocampal naming involvement. On the other hand, critical naming sites have been found in anterior, lateral temporal (i.e. extra-hippocampal) neocortex, the region typically removed with ‘standard’ TLE resection. We, therefore, speculated that the relative preservation of naming in post-operative HS patients might reflect cortical reorganization of language to areas outside this region. Using pre-resection electrical stimulation mapping, we compared the topography of auditory and visual naming sites in 12 patients with HS and 12 patients without structural brain pathology. Consistent with previous work, non-HS patients exhibited post-operative naming decline, whereas HS patients did not. As hypothesized, HS patients had proportionally fewer overall naming sites in anterior temporal cortex, the region typically removed with standard anterior temporal resection, whereas non-HS patients exhibited a more even distribution of naming sites in anterior and posterior temporal regions ( P = 0.03). Although both groups exhibited the previously reported pattern of auditory naming sites anterior to visual naming sites, auditory naming sites had a significantly more posterior distribution in HS patients ( P = 0.02). Additionally, non-HS patients exhibited a greater proportion of visual naming sites above the superior temporal sulcus, whereas visual naming sites in HS patients were scattered across superior and inferior temporal cortex. Results suggest that preserved naming ability in HS patients following anterior temporal resection might be attributable, at least in part, to intrahemispheric reorganization of language in response to the likely, early development of sclerosis in the medial temporal region. Furthermore, their more posterior distribution of naming sites is consistent with the more anterior propagation of EEG discharges in TLE. These results hold theoretical implications regarding the role of the dominant hippocampus in determining the cortical representation of semantic and lexical information, and raise questions regarding the specific roles of medial and lateral temporal cortex in targeted word retrieval. The different patterns of naming areas identified in patients with and without HS may also carry clinical implications, potentially improving efficiency during the time-constrained process of stimulation mapping.

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