Emotional Facial Expression Detection in the Peripheral Visual Field

BACKGROUND: In everyday life, signals of danger, such as aversive facial expressions, usually appear in the peripheral visual field. Although facial expression processing in central vision has been extensively studied, this processing in peripheral vision has been poorly studied. METHODOLOGY/PRINCIPAL FINDINGS: Using behavioral measures, we explored the human ability to detect fear and disgust vs. neutral expressions and compared it to the ability to discriminate between genders at eccentricities up to 40°. Responses were faster for the detection of emotion compared to gender. Emotion was detected from fearful faces up to 40° of eccentricity. CONCLUSIONS: Our results demonstrate the human ability to detect facial expressions presented in the far periphery up to 40° of eccentricity. The increasing advantage of emotion compared to gender processing with increasing eccentricity might reflect a major implication of the magnocellular visual pathway in facial expression processing. This advantage may suggest that emotion detection, relative to gender identification, is less impacted by visual acuity and within-face crowding in the periphery. These results are consistent with specific and automatic processing of danger-related information, which may drive attention to those messages and allow for a fast behavioral reaction

How Does Reward Compete with Goal-Directed and Stimulus-Driven Shifts of Attention?

Epub ahead of printIn order to behave adaptively, attention can be directed in space either voluntarily (i.e. endogenously) according to strategic goals, or involuntarily (i.e. exogenously) through reflexive capture by salient or novel events. The emotional or motivational values of stimuli can also influence attentional orienting. However, little is known about how reward-related effects compete or interact with endogenous and exogenous attention mechanisms. Here we designed a visual search paradigm in which goal-driven and stimulus-driven shifts of attention were manipulated by classic spatial cueing procedures, while an irrelevant, but previously rewarded stimulus also appeared as a distractor and hence competed with both types of spatial attention during search. Our results demonstrated that stimuli previously associated with a high monetary reward received higher attentional priority in the subsequent visual search task, even though these stimuli and reward were no longer task-relevant, mitigating the attentional orienting induced by both endogenous and exogenous cues

How does reward compete with goal-directed and stimulus-driven shifts of attention?

In order to behave adaptively, attention can be directed in space either voluntarily (i.e. endogenously) according to strategic goals, or involuntarily (i.e. exogenously) through reflexive capture by salient or novel events. The emotional or motivational values of stimuli can also influence attentional orienting. However, little is known about how reward-related effects compete or interact with endogenous and exogenous attention mechanisms. Here we designed a visual search paradigm in which goal-driven and stimulus-driven shifts of attention were manipulated by classic spatial cueing procedures, while an irrelevant, but previously rewarded stimulus also appeared as a distractor and hence competed with both types of spatial attention during search. Our results demonstrated that stimuli previously associated with a high monetary reward received higher attentional priority in the subsequent visual search task, even though these stimuli and reward were no longer task-relevant, mitigating the attentional orienting induced by both endogenous and exogenous cues

PRZEDRUK POLSKIEGO TŁUMACZENIA ARTYKUŁU ZA ZGODĄ INTERNATIONAL ASSOCIATION FOR THE STUDY OF PAIN (IASP) - PAIN 154 (2013) 2691-2699 Migrenowe bóle głowy i ból o cechach neuropatycznych: schorzenia współistniejące u chorych na stwardnienie rozsiane

We conducted a postal survey to assess the prevalence and characteristics of neuropathic pain and migraine in a cohort of multiple sclerosis (MS) patients. Of the 1300 questionnaires sent, 673 could be used for statistical analysis. Among the respondents, the overall pain prevalence in the previous month was 79%, with 51% experiencing pain with neuropathic characteristics (NCs) and 46% migraine. MS patients with both migraine and NC pain (32% of the respondents) reported more severe pain and had lower health-related quality of life than MS patients with either migraine or NC pain. Pain intensity in MS patients with migraine was moderate (6.0±0.1). Migraine was mostly episodic, but headaches were occurring on P15 days per month in 15% of those with migraine. MS patients with migraine were younger and had shorter disease durations than those with NC pain. NC pain was most often located in the extremities, back and head, and was frequently described as tingling and pins-and-needles. The intensity of NC pain was low to moderate (4.9±0.1), but positively correlated with the number of painful body sites. Nonetheless, patients with NC pain were more disabled (with a higher Expanded Disability Status Scale and pain interference index) than patients with migraine. Migraine, but not NC pain, was associated with age, disease duration, relapsing-remitting course, and interferon-beta treatment. This suggests that NC pain and migraine are mediated by different mechanisms. Therefore, pain mechanisms that specifically operate in MS patients need to be characterized to design optimal treatments for these individuals.Przeprowadziliśmy listowne badanie kwestionariuszowe w celu oceny częstości występowania i charakterystyki bólu neuropatycznego i migreny w kohorcie chorych na stwardnienie rozsiane (SR). Spośród wysłanych 1300 kwestionariuszy 673 nadawało się do analizy statystycznej. Ogólna częstość występowania bólu u respondentów w ciągu miesiąca poprzedzającego badanie wyniosła 79%; 51% badanych odczuwało ból o cechach neuropatycznych (BN), a 46% - ból migrenowy. Chorzy odczuwający zarówno ból migrenowy jak i BN (32% respondentów) zgłaszali większe natężenie bólu i gorszą jakość życia związaną ze stanem zdrowia niż pacjenci ze SR odczuwający tylko jeden z tych bólów. Natężenie bólu u chorych na SR i migrenę było umiarkowane (6,0±0,1). Migrena w większości przypadków miała charakter epizodyczny, ale u 15% osób z migreną bóle głowy występowały ≥15 dni w miesiącu. Chorzy na SR i na migrenę byli młodsi i chorowali krócej niż pacjenci z BN. Ból o charakterze neuropatycznym najczęściej umiejscowiony był w kończynach, plecach i głowie; często opisywany był jako mrowienie lub kłucie. Nasilenie BN było małe lub umiarkowane (4,9±0,1) ale korelowało z liczbą objętych bólem części ciała. Niemniej jednak pacjenci z BN byli bardziej niesprawni (mieli większą punktację w Expanded Disability Status Scale i w Pain Interference Index) niż pacjenci z migreną. W przeciwieństwie do BN, migrena była powiązana z wiekiem, czasem trwania choroby, postacią nawracająco-zwalniającą choroby oraz z leczeniem interferonem beta. Wskazuje to na odrębne mechanizmy BN i migreny. W związku z tym wydaje się konieczne scharakteryzowanie mechanizmów bólu, które działają swoiście u chorych na SR w celu opracowania optymalnego leczenia tych pacjentów

Subdivision of the occipital lobes:An anatomical and functional MRI connectivity study

International audienceExploring brain connectivity is fundamental to understanding the functional architecture of the cortex. In our study we employed tractography-based parcellation, combined with the principal component analysis statistical framework, to divide the occipital lobes into seven areas in a group of eighteen healthy participants. Tractography-based parcellation is a method based on diffusion imaging tractography, which segregates the living human brain into distinctive areas showing sharp differences in their anatomical connectivity. The results were compared to covarying functional networks involving distinct areas within the occipital lobes, that we obtained using resting state functional magnetic resonance imaging (fMRI), as well as to other existing subdivisions of the occipital lobes. Our results showed similarities with functional imaging data in healthy controls and cognitive profiles in brain-damaged patients, although several differences with cytoarchitectonic, myelogenetic, myeloarchitectonic and functional maps were reported. While the similarities are encouraging, the potential validity and limitations of the differences observed are discussed. Taken together these results suggest that tractography-based parcellation may provide a new promising anatomical subdivision of the living human brain based on its anatomical connectivity, which may benefit the understanding of clinical-neuroanatomical dissociations and functional neuroimaging results

Group source analysis.

<p>The student-t statistic 3D map resulting for the group source analysis are thresholded by the corresponding p-value<0.01. During the first 130 ms, not-consciously perceived peripheral fearful faces enhanced the neuronal activity in the right anterior medial temporal lobe, including parahippocampal gyrus and amygdala.</p

Brain areas more activated by fearful than by neutral peripherally presented faces in the three analyzed time windows.

<p>For each activation cluster, the Talairach coordinates correspond to the voxel of maximal intensity obtained after the ERB analyses, the volumes are expressed in cm³. The threshold is set at uncorrected p<0.01 (*p<0.005, **p<.001).</p

Brain areas more activated by fearful than by neutral centrally presented faces in the three analyzed time windows.

<p>For each activation cluster, the Talairach coordinates correspond to the voxel of maximal intensity obtained after the ERB analyses, the volumes are expressed in cm³. The threshold is set at uncorrected p<0.01 (*p<0.005, **p<.001).</p

Sensor responses averaged across subjects and conditions.

<p>Event-related beamformer source analyses were performed in three 50 ms time windows (grey) surrounding the three major peaks. Magnetic activity maps represent the sensor activity for each maximum peak amplitude.</p

Example of trial.

<p>Each trial started with two scrambled faces and a fearful or neutral face presented for 33 ms, centrally or peripherally, immediately masked by 3 neutral faces. After a variable delay the target stimulus was appearing. The subject was asked to press a button when a happy face was occurring.</p