Who is that? Brain networks and mechanisms for identifying individuals

Social animals can identify conspecifics by many forms of sensory input. However, whether the neuronal computations that support this ability to identify individuals rely on modality-independent convergence or involve ongoing synergistic interactions along the multiple sensory streams remains controversial. Direct neuronal measurements at relevant brain sites could address such questions, but this requires better bridging the work in humans and animal models. Here, we overview recent studies in nonhuman primates on voice and face identity-sensitive pathways and evaluate the correspondences to relevant findings in humans. This synthesis provides insights into converging sensory streams in the primate anterior temporal lobe (ATL) for identity processing. Furthermore, we advance a model and suggest how alternative neuronal mechanisms could be tested

One-loop Yukawas on Intersecting Branes

We calculate Yukawa interactions at one-loop on intersecting D6 branes. We demonstrate the non-renormalization theorem in supersymmetric configurations, and show how Yukawa beta functions may be extracted. In addition to the usual logarithmic running, we find the power-law dependence on the infra-red cut-off associated with Kaluza-Klein modes. Our results may also be used to evaluate coupling renormalization in non-supersymmetric cases.Comment: 48 pages, 9 figures; minor corrections, JHEP styl

Resolution of Acute Hydrocephalus and Migration of Neurocysticercosis Cyst with External Ventricular Drainage

Neurocysticercosis is endemic in the developing world, but is becoming more common in the US due to immigration. A 24-year-old man presented with acute hydrocephalus and headaches, nausea, and vomiting. Head CT revealed a 3rd ventricular cyst and immunological studies were suggestive of neurocysticercosis. EVD placement resulted in migration of the cyst interiorly and superiorly with return of normal CSF flow by MRI and resolution of symptoms. Review of this condition is important given increasing incidence in the United States

Unilateral Handgrip Holds to Failure Result in Sex-Dependent Contralateral Facilitation

There can be differences in fatigue characteristics between men and women. In some cases, these differences may be manifested in unique strength responses in the fatigued and non-fatigued limbs following a unilateral fatiguing task. PURPOSE: This study examined changes in maximal voluntary isometric contraction (MVIC) force following dominant (Dm) and nondominant (NDm) unilateral, isometric handgrip holds to failure (HTF) for the exercised ipsilateral (IPS) and non-exercised contralateral (CT) limbs. Sex- and hand- (Dm vs NDm) dependent responses in HTF time, performance fatiguability (PF, %D in MVIC) for the exercised IPS limb, as well as changes in MVIC force for the CT limb following the HTF were examined. METHODS: Ten men and 10 women (Age = 22.2 yrs) performed an isometric, HTF at 50% MVIC for the Dm and NDm hand on separate days. Prior to, and immediately after the HTF, a MVIC was performed on the IPS and CT limbs, in a randomized order. A 2 (hand [Dm, NDm]) x 2 (limb [IPS, CON]) x 2 (time [pre-HTF, post-HTF]) x 2 (sex [men, women]) mixed-model ANOVA was used to examine the MVIC force (kg) and a 2 (hand [Dm, NDm]) x 2 (sex [men, women]) mixed-model ANOVA was used to examine time for the HTF. RESULTS: The Dm (130.3 ± 36.8s) HTF (collapsed across sex) was significantly longer (p = 0.002) than the NDm (112.1 ± 34.3s). The men (collapsed across hand) demonstrated IPS (%Δ= 22.9 ± 10.8%) PF and CT facilitation (%Δ= -6.1 ±6.9%) following the HTF, while the women demonstrated differences in PF between the Dm and NDm hands for the IPS (%Δ Dm = 28.0 ± 9.4%; NDm = 32.3% ± 10.1%; p = 0.027), but not the CT limb (%Δ Dm= -1.6 ± 5.7%; NDm = 1.7 ± 5.9%). CONCLUSIONS: Despite the greater fatigue resistance for the Dm compared to the NDm hand, there were no differences in PF for the IPS side for the men, but lesser IPS PF for Dm compared to NDm hand for the women. The cross-over facilitation of the CT limb for men, but not women, following a unilateral, isometric handgrip HTF may be related to post-activation potentiation

Treatment of Endovascular Coil and Stent Migration Using the Merci Retriever: Report of Three Cases

Background. Coil and stent migration is a potentially catastrophic complication in endovascular neurosurgery, which may lead to cerebral thromboembolism. Techniques for removing migrated coil and stent are not well established. Methods and Results. We present three cases in which coil or stent migration occurred during endovascular embolization of a cerebral aneurysm. The Merci Retrievers were used successfully in all cases to remove the displaced foreign bodies. Technical details are described. Conclusion. The Merci Retriever device can be utilized successfully for removal of migrated coils and stents in endovascular neurosurgery

Infrared alignment of SUSY flavor structures

The various experimental bounds on flavor-changing interactions severely restrict the low-energy flavor structures of soft supersymmetry breaking parameters. In this work, we show that with a particular assumption of Yukawa couplings, the fermion mass and sfermion soft mass matrices are simultaneously diagonalized by common mixing matrices and we then obtain an alignment solution for the flavor problems. The required condition is generated by renormalization group evolutions and achieved at low-energy scale independently of high-energy structures of couplings. In this case, the diagonal entries of the soft scalar mass matrices are determined by gaugino and Higgs soft masses. We also discuss possible realizations of this scenario and the characteristic sparticle spectrum in the models.Comment: 18 pages, 1 figur

The Number of Supernovae from Primordial Stars in the Universe

Recent simulations of the formation of the first luminous objects in the universe predict isolated very massive stars to form in dark matter halos with virial temperatures large enough to allow significant amounts of molecular hydrogen to form. We construct a semi-analytic model based on the Press-Schechter formalism and calibrate the minimum halos mass that may form a primordial star with the results from extensive adaptive mesh refinement simulations. The model also includes star formation in objects with virial temperatures in excess of ten thousand Kelvin. The free parameters are tuned to match the optical depth measurements by the WMAP satellite. The models explicitly includes the negative feedback of the destruction of molecular hydrogen by a soft UV background which is computed self-consistently. We predict high redshift supernova rates as one of the most promising tools to test the current scenario of primordial star formation. The supernova rate from primordial stars peaks at redshifts ~20. Using an analytic model for the luminosities of pair-instability supernovae we predict observable magnitudes and discuss possible observational strategies. Such supernovae would release enough metals corresponding to a uniform enrichment to a few hundred thousands of solar metalicity. If some of these stars produce gamma ray bursts our rates will be directly applicable to understanding the anticipated results from the SWIFT satellite. This study highlights the great potential for the James Webb space telescope in probing cosmic structure at redshifts greater than 20.Comment: 12 pages, 8 figures, submitted to Astrophysical Journa

Phaseâ amplitude coupling between interictal highâ frequency activity and slow waves in epilepsy surgery

ObjectiveWe hypothesized that the modulation index (MI), a summary measure of the strength of phaseâ amplitude coupling between highâ frequency activity (>150 Hz) and the phase of slow waves (3â 4 Hz), would serve as a useful interictal biomarker for epilepsy presurgical evaluation.MethodsWe investigated 123 patients who underwent focal cortical resection following extraoperative electrocorticography recording and had at least 1 year of postoperative followâ up. We examined whether consideration of MI would improve the prediction of postoperative seizure outcome. MI was measured at each intracranial electrode site during interictal slowâ wave sleep. We compared the accuracy of prediction of patients achieving International League Against Epilepsy class 1 outcome between the full multivariate logistic regression model incorporating MI in addition to conventional clinical, seizure onset zone (SOZ), and neuroimaging variables, and the reduced logistic regression model incorporating all variables other than MI.ResultsNinety patients had class 1 outcome at the time of most recent followâ up (mean followâ up = 5.7 years). The full model had a noteworthy outcome predictive ability, as reflected by regression model fit R2 of 0.409 and area under the curve (AUC) of receiver operating characteristic plot of 0.838. Incomplete resection of SOZ (P < 0.001), larger number of antiepileptic drugs at the time of surgery (P = 0.007), and larger MI in nonresected tissues relative to that in resected tissue (P = 0.020) were independently associated with a reduced probability of class 1 outcome. The reduced model had a lower predictive ability as reflected by R2 of 0.266 and AUC of 0.767. Anatomical variability in MI existed among nonepileptic electrode sites, defined as those unaffected by magnetic resonance imaging lesion, SOZ, or interictal spike discharges. With MI adjusted for anatomical variability, the full model yielded the outcome predictive ability of R2 of 0.422, AUC of 0.844, and sensitivity/specificity of 0.86/0.76.SignificanceMI during interictal recording may provide useful information for the prediction of postoperative seizure outcome.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/146440/1/epi14544_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/146440/2/epi14544.pd

Fantasy-driven versus contact-driven users of child sexual exploitation material: offender classification and implications for their risk assessment

Since the advent of the internet, convictions for the possession, display, trading and distribution of child sexual exploitation material (CSEM) have risen steadily, but little is known about the appropriate assessment and treatment of this offender group, especially in regards to their risk of reoffending. It has been suggested that a conceptual distinction of fantasy- vs. contact-driven CSEM users might be of merit. Sixty-eight offenders recruited from sex offender treatment providers were assessed via an anonymous computer survey including a variety of clinical and risk-related variables; the findings showed differences in the psychological profiles between CSEM users and contact child sex offenders. Numerical and spatial methods were employed to identify subgroups of CSEM users; these confirmed the two-fold distinction of fantasy vs. contact driven offending. The spatial representation of participants identified three dimensions as crucial in the classification of these subgroups: direct sexual contact with a minor, possession of fantasy-generating material, and social contact with other users with a sexual interest in minors, potentially differentiating distinct offender subgroups with different risks and needs. The current study informed the development of an empirical model of CSEM users that could aid in the assessment of risk of reoffending and cross-over to contact sex offending

A Study on the Non-perturbative Existence of Yang-Mills Theories with Large Extra Dimensions

Pure lattice SU(2) Yang-Mills theory in five dimensions is considered, where an extra dimension is compactified on a circle. Monte-Carlo simulations indicate that the theory possesses a continuum limit with a non-vanishing string tension if the compactification radius is smaller than a certain value $R_M$ which is $O(1/10)$ of the inverse of the square root of the string tension. We verify non-perturbatively the power-law running of gauge coupling constant. Our method can be applied to the investigation of continuum limits in other higher-dimensional gauge theories.Comment: 42 pages, 20 figures, 2 table