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Dual route models of reading suggest there are 2 pathways for reading words: an orthographic-lexical pathway, used to read familiar regular words and exception words, and a grapheme-to-phoneme-conversion-(GPC)-sublexical pathway, used to read unfamiliar regular words, pseudohomophones (PHs), and nonwords. It is unclear, however, whether PHs activate lexical and semantic representations without intention in the GPC-sublexical pathway to the same extent as words along the orthographic-lexical pathway. The present study explored this by introducing a novel condition, color pseudohomophone associates (CPHAs; e.g., "skigh"), in 3 experiments using the Stroop paradigm. Experiment 1 examined 4 types of stimuli: color words (CWs), color word associates (CWAs), color PHs (CPHs), and color PH associates (CPHAs), in a mixed list context. Significant Stroop effects were found for all 4 types of stimuli. To ensure the robustness of this effect, Experiment 2 was conducted using pure list contexts whereby participants received only word stimuli (e.g., CWs, CWAs) or only PH stimuli (e.g., CPHs, CPHAs). The results replicated those of Experiment 1, suggesting that CPHAs activate lexical and semantic representations without intention in the GPC-sublexical pathway. Experiment 3 added 2 novel conditions: color exception word associates (which can only be pronounced correctly using the orthographic-lexical pathway) to compare the effects obtained with color exception PH associates (which rely on the GPC-sublexical pathway for correct pronunciation). Stroop effects of similar magnitude were found for both types of stimuli, suggesting lexical and semantic representations are accessed without intention in either reading pathway to a similar degree. Implications for models of reading are discussed.

Neurobiology of reading research has yet to explore whether reliance on the ventral-lexical stream during word reading can be enhanced by the instructed reading strategy, or whether it is impervious to such strategies. We examined Instructions: "name all" vs. "name words" (based on spelling), Word Type: "regular words" vs. "exception words", and Word Frequency (WF) in print (log[subscript 10] HAL WF) in an experiment while measuring fMRI BOLD and overt naming reaction time (RT) simultaneously. Instructions to "name words" increased overall reliance on the ventral-lexical stream, as measured by visible BOLD activation and the WF effect on RT, with regular words showing the greatest effects as a function of this reading strategy. Furthermore, the pattern of joint effects of these variables on RT supports the notion of cascaded, not parallel, processing. These results can be accommodated by dual-stream cascaded models of reading, and present a challenge to single-mechanism parallel processing models. (Contains 5 figures.)

• Non-paretic high-force contractions promote ipsilesional motor cortex activation. • Brain activation was similar between healthy controls and participants with stroke. • Non-paretic high-force contractions may provide a boost for ipsilesional plasticity. Stroke is a leading cause of severe disability that often presents with unilateral motor impairment. Conventional rehabilitation approaches focus on motor practice of the affected limb and aim to suppress brain activity in the contralesional hemisphere. Conversely, exercise of the less-affected limb promotes contralesional brain activity which is typically viewed as contraindicated in stroke recovery due to the interhemispheric inhibitory influence onto the ipsilesional hemisphere. Yet, high-force unimanual handgrip contractions are known to increase ipsilateral brain activation in control participants, and it remains to be determined if high-force contractions with the less-affected limb would promote ipsilateral brain activation in participants with stroke (i.e., the ipsilesional hemisphere). Therefore, this study aimed to determine how parametric increases in handgrip force during repeated contractions with the less-affected limb impacts brain activity bilaterally in participants with stroke and in a cohort of neurologically intact controls. Participants performed repeated submaximal contractions at 25%, 50%, and 75% of their maximum voluntary contraction during separate functional magnetic resonance imaging brain scans. Brain activation during the tasks was quantified as the percent change from resting levels. In this study, higher force contractions were found to increase brain activation in the ipsilesional (stroke)/ipsilateral (controls) hemisphere in both groups (p =.002), but no between group differences were observed. These data suggest that high-force exercise with the less-affected limb may promote ipsilesional cortical plasticity to promote motor recovery of the affected-limb in participants with stroke. [ABSTRACT FROM AUTHOR]

We used functional magnetic resonance imaging (fMRI) to examine the brain regions associated with the effect of congruency between rhythmic stress and syllabic stress on reading aloud (Gould et al., 2016). The region of particular interest was the putamen, which has been shown to be involved in speech processing, rhythm processing, and predicting upcoming events. The task involved naming words that placed the stress on either the first or second syllable (practice versus police), as well as their corresponding pseudohomophones (praktis versus poleese) that were preceded by either a congruent or incongruent rhythmic prime. The fMRI results revealed that a network involving the putamen is involved, and the behavioural results demonstrated that a rhythmic prime matched to the syllabic stress aids reading processes of both words and PHs. Implications for neurobiological models of reading, as well as clinical applications (e.g. speech rehabilitation in Parkinson’s disease) are discussed. [ABSTRACT FROM PUBLISHER]

The central aim of this experiment was to explore the connection between rhythm and reading processes by examining whether reading aloud is affected by the presentation of a rhythmic prime that was either congruent or incongruent with the syllabic stress of the target letter string. The targets were words that placed the stress on either the first or second syllable (practice vs. police), as well as their corresponding pseudohomophones (PHs) (praktis vs. poleese). The results demonstrated that naming reaction times were faster for PHs when the rhythmic prime was congruent with the syllabic stress, and slower when the rhythmic prime was incongruent. These results are taken to suggest that PHs showed a larger effect given that they must be phonetically decoded. The congruency by stimulus type interaction suggests that their effects reflect at least one common stage of processing, namely grapheme to phoneme translation. In general, these results indicate that a rhythmic prime matched to the syllabic stress of a letter string that requires phonetic decoding aids sublexical reading processes, which has important implications for allowing models of reading to account for rhythm processes. The current paradigm may also reveal potential remedial applications for treating speech deficits in patient populations, such as Parkinson's disease, stuttering, aphasia, and dyslexia. [ABSTRACT FROM AUTHOR]

We report a 55-year-old, right-handed patient with intractable left temporal lobe epilepsy, who previously had a partial left temporal lobectomy. The patient could talk during seizures, suggesting that he might have language dominance in the right hemisphere. Presurgical fMRI localization of language processing including reading of exception and regular words, pseudohomophones, and dual meaning words confirmed the clinical hypothesis of right language dominance, with only small amounts of activation near the planned surgical resection and, thus, minimal eloquent cortex to avoid during surgery. Postoperatively, the patient was rendered seizure-free without speech deficits.