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This study investigated effects of rate reduction and emphatic stress cues on second formant (F2) trajectories and articulatory movements during diphthong production in 11 typically developing school-aged children. F2 extent increased in slow and emphatic stress conditions, and tongue and jaw displacement increased in the emphatic stress condition compared to habitual speech. Tongue displacement significantly predicted F2 extent across speaking conditions. Results suggest that slow rate and emphatic stress cues induce articulatory and acoustic changes in children that may enhance clarity of the acoustic signal. Potential clinical implications for improving speech in children with dysarthria are discussed.

Before the 33rd Annual International Society for Heart and Lung Transplantation conference, there was significant intercenter variability in definitions of primary graft dysfunction (PGD). The incidence, risk factors, and outcomes of consensus-defined PGD warrant further investigation. We retrospectively examined 448 adult cardiac transplant recipients at our institution from 2005 to 2017. Patient and procedural characteristics were compared between PGD cases and controls. Multivariable logistic regression was used to model PGD and immediate postoperative high-inotrope requirement for hypothesized risk factors. Patients were followed for a mean 5.3 years to determine longitudinal mortality. The incidence of PGD was 16.5%. No significant differences were found with respect to age, sex, race, body mass index, predicted heart mass mismatch, pretransplant amiodarone therapy, or pretransplant mechanical circulatory support (MCS) between recipients with PGD versus no PGD. Each 10 minute increase in ischemic time was associated with 5% greater odds of PGD (OR = 1.05 [95% CI, 1.00-1.10]; p = 0.049). Pretransplant MCS, predicted heart mass mismatch ≥30%, and pretransplant amiodarone therapy were associated with high-immediate postoperative inotropic requirement. The 30 day, 1 year, and 5 year mortality for patients with PGD were 28.4%, 38.0%, and 45.8%, respectively, compared with 1.9%, 7.1%, and 21.5% for those without PGD (log-rank, p < 0.0001). PGD heralded high 30 day, 1 year, and 5 year mortality. Pretransplant MCS, predicted heart mass mismatch, and amiodarone exposure were associated with high-inotrope requirement, while prolonged ischemic time and multiple perioperative transfusions were associated with consensus-defined PGD, which may have important clinical implications under the revised United Network for Organ Sharing allocation system.

Reliable prediction of epileptic seizures is of prime importance as it can drastically change the quality of life for patients. This study aims to propose a real-time low computational approach for the prediction of epileptic seizures and to present an efficient hardware implementation of this approach for portable prediction systems. Three levels of feature extraction are performed to characterize the pre-ictal activities of the EEG signal. In the first-level, the line length algorithm is applied to the pre-ictal region. The features obtained in the first-level are mathematically integrated to extract the second-level features and then the line lengths of the second-level features are calculated to obtain our third-level feature. The third-level information is compared with predefined threshold levels to make a decision on whether the extracted characteristics are relevant to a seizure occurrence or not. The validity of this algorithm was tested by EEG recordings in the CHB-MIT database (97 seizures, 834.224 h) for 19 epileptic patients. The results showed that the average sensitivity was 90.62%, the specificity was 88.34%, the accuracy was 88.76% with the average false prediction rate as low as 0.0046 h−1, and the average prediction time was 23.3 min. The low computational complexity is the superiority of the proposed approach, which provides a technologically simple but accurate way of predicting epileptic seizures and enables hardware implantable devices.

We investigated the neural correlates of pleasure induced by listening to highly pleasant and neutral musical excerpts using electroencephalography (EEG). Power spectrum analysis of EEG data showed a distinct gradual change in the power of low-frequency oscillations in response to highly pleasant, but not neutral, musical excerpts. Specifically, listening to highly pleasant music was associated with (i) relatively higher oscillatory activity in the theta band over the frontocentral (FC) area and in the alpha band over the parieto-occipital area, and (ii) a gradual increase in the oscillatory power over time. Correlation analysis between behavioral and electrophysiological data revealed that theta power over the FC electrodes was correlated with subjective assessment of pleasantness while listening to music. To study the link between attention and positive valence in our experiments, volunteers performed a delayed match-to-sample memory task while listening to the musical excerpts. The subjects’ performances were significantly lower under highly pleasant conditions compared to neutral conditions. Listening to pleasant music requires higher degrees of attention, leading to the observed decline in memory performance. Gradual development of low-frequency oscillations in the frontal and posterior areas may be at least partly due to gradual recruitment of higher levels of attention over time in response to pleasurable music.

Face-selective neurons in the inferior temporal (IT) cortex respond to faces by either increasing (ENH) or decreasing (SUP) their spiking activities compared with their baseline. Although nearly half of IT face neurons are selectively suppressed by face stimulation, their role in face representation is not clear. To address this issue, we recorded the spiking activities and local field potential (LFP) from IT cortex of three monkeys while they viewed a large set of visual stimuli. LFP high-gamma (HG-LFP) power indicated the presence of both ENH and SUP face-selective neural clusters in IT cortex. The magnitude of HG-LFP power of the recording sites was correlated with the magnitude of change in the evoked spiking activities of its constituent neurons for both ENH and SUP face clusters. Spatial distribution of the ENH and SUP face clusters suggests the presence of a complex and heterogeneous face hypercluster organization in IT cortex. Importantly, ENH neurons conveyed more face category and SUP neurons conveyed more face identity information at both the single-unit and neuronal population levels. Onset and peak of suppressive single-unit, neuronal population, and HG-LFP power activities lagged those of the ENH ones. These results demonstrate that IT neuronal code for face representation is optimized by increasing sparseness through selective suppression of a subset of face neurons. We suggest that IT cortex contains spatial clusters of both ENH and SUP face neurons with distinct specialized functional role in face representation.

Objective To report the establishment of a new center for deep brain stimulation (DBS) as a surgical treatment for Parkinson disease and the surgical outcomes, from 2014 to 2017 in Shiraz, Southern Iran. Methods A new treatment program was established in Shiraz through a multidisciplinary team in 2014. Thirty-four patients underwent implantation of subthalamic nucleus (STN) electrodes during the last 3 years. Twenty-five patients fulfilled the minimum 6-month follow-up criteria. The baseline Unified Parkinson Disease Rating Scale (UPDRS) was assessed 1 month before surgery in both off-medication and on-medication states by a movement disorder neurologist. To evaluate the outcomes, subscores of the UPDRS were assessed in all patients before surgery and at least 6 months after the operation. Results All 25 patients had advanced Parkinson disease categorized as stage 3 or 4 using the Hoehn and Yahr scale. STN DBS resulted in a dramatic improvement in motor function of most patients. A reduction in dopaminergic medication dosage (average 60% reduction) was observed. The mean improvement was 40% in UPDRS II and 67% in UPDRS III. No surgical or hardware complications were observed. Stimulation-related adverse effects, including increased falling and worsening of speech, occurred in a few patients after surgery. Most of the patients experienced weight gain after surgery. Conclusions Bilateral STN DBS is a satisfactory and safe treatment for carefully selected patients with advanced Parkinson disease. According to the results, the procedure can be performed safely and with comparable results in developing countries around the world.

Selective Dorsal Rhizotomy (SDR) is a neurosurgical procedure currently used as a surgical treatment of children with spasticity in their legs. In SDR, the dorsal roots from L2 to S1 or S2 is partially sectioned. The primary goal of SDR is to reduce spasticity and improve the range of movement with preservation of muscle strength. The dorsal roots involved in spasticity are identified on the basis of intraoperative electrophysiological stimulation. Currently, SDR is most commonly performed for the treatment of spastic cerebral palsy in children. We report an 8-year-old child with spastic cerebral palsy who underwent intraoperative neurophysiology monitoring during SDR for treating his spasticity. Before the operation, patient’s examination revealed more spasticity at the lower extremities, mild spasticity at the upper extremities, and occurrence of fixed contracture of his both ankle joints. Intraoperative neuromonitoring (consisting of motor evoked als, direct nerve root stimulation, and free run electromyography) was performed during the operation. Electrophysiological monitoring was initially used to help differentiate between the ventral and dorsal roots and cutting the abnormal sensory rootlets. After the operation, his motor power of the lower extremities in the proximal and distal muscles was 4 out of 5, his saddle sensation became normal, and there was no urinary and stool incontinency. Four weeks after the surgery, he could walk about 10 m without help. His examination at 2 and 4 weeks after the operation showed was no sign of sensory deficits, urinary, or stool incontinency. Two months after the operation, the patient could walk independently without help while before the operation, he could not.

We measured the fast temporal dynamics of face processing simultaneously across the human temporal cortex (TC) using intracranial recordings in eight participants. We found sites with selective responses to faces clustered in the ventral TC, which responded increasingly strongly to marine animal, bird, mammal, and human faces. Both face-selective and face-active but non-selective sites showed a posterior to anterior gradient in response time and selectivity. A sparse model focusing on information from the human face-selective sites performed as well as, or better than, anatomically distributed models when discriminating faces from non-faces stimuli. Additionally, we identified the posterior fusiform site (pFUS) as causally the most relevant node for inducing distortion of conscious face processing by direct electrical stimulation. These findings support anatomically discrete but temporally distributed response profiles in the human brain and provide a new common ground for unifying the seemingly contradictory modular and distributed modes of face processing., Neuronal populations in the temporal cortex fire show increased activity in response to face stimuli. Here, the authors show using human intracranial recordings that face perception involves anatomically discrete but temporally distributed response profiles in the human ventral temporal cortex.