The speed of morality: a high-density electrical neuroimaging study

2012 ◽  
Vol 108 (11) ◽  
pp. 3068-3072 ◽  
Author(s):  
Jean Decety ◽  
Stephanie Cacioppo

Neuroscience research indicates that moral reasoning is underpinned by distinct neural networks including the posterior superior temporal sulcus (pSTS), amygdala, and ventromedial prefrontal cortex, which support communication between computational systems underlying affective states, cognitions, and motivational processes. To characterize real-time neural processing underpinning moral computations, high-density event-related potentials were measured in participants while they viewed short, morally laden visual scenarios depicting intentional and accidental harmful actions. Current source density maxima in the right pSTS as fast as 62 ms poststimulus first distinguished intentional vs. accidental actions. Responses in the amygdala/temporal pole (122 ms) and ventromedial prefrontal cortex (182 ms) were then evoked by the perception of harmful actions, indicative of fast information processing associated with early stages of moral cognition. Our data strongly support the notion that intentionality is the first input to moral computations. They also demonstrate that emotion acts as a gain antecedent to moral judgment by alerting the individual to the moral salience of a situation and provide evidence for the pervasive role of affect in moral sensitivity and reasoning.

1999 ◽  
Vol 11 (6) ◽  
pp. 598-609 ◽  
Author(s):  
Charan Ranganath ◽  
Ken A. Paller

Previous neuropsychological and neuroimaging results have implicated the prefrontal cortex in memory retrieval, although its precise role is unclear. In the present study, we examined patterns of brain electrical activity during retrieval of episodic and semantic memories. In the episodic retrieval task, participants retrieved autobiographical memories in response to event cues. In the semantic retrieval task, participants generated exemplars in response to category cues. Novel sounds presented intermittently during memory retrieval elicited a series of brain potentials including one identifiable as the P3a potential. Based on prior research linking P3a with novelty detection and with the frontal lobes, we predicted that P3a would be reduced to the extent that novelty detection and memory retrieval interfere with each other. Results during episodic and semantic retrieval tasks were compared to results during a task in which subjects attended to the auditory stimuli. P3a amplitudes were reduced during episodic retrieval, particularly at right lateral frontal scalp locations. A similar but less lateralized pattern of frontal P3a reduction was observed during semantic retrieval. These findings support the notion that the right prefrontal cortex is engaged in the service of memory retrieval, particularly for episodic memories.


1990 ◽  
Vol 2 (3) ◽  
pp. 258-271 ◽  
Author(s):  
Marta Kutas ◽  
Steven A. Hillyard ◽  
Bruce T. Volpe ◽  
Michael S. Gazzaniga

The lateral distribution of the P300 component of the event-related brain potential (ERP) was studied in five epileptic patients whose corpus callosum had been surgically sectioned and in seven neurologically intact controls. The P300 was elicited in an auditory “oddball” task using high- and low-pitched tones and in a visual oddball task in which target words were presented either to the left or right visual fields, or to both fields simultaneously. Commissurotomy altered the normal pattern of bilaterally symmetrical P300 waves over the left and right hemispheres, but in a different manner for auditory and visual stimuli. The auditory P3 to binaural tones was larger in amplitude over the right than the left hemisphere for the patients. In the visual task, the laterality of the P300 varied with the visual field of the target presentation. Left field targets elicited much larger P300 amplitudes over the right than the left hemisphere, as did bilateral targets. In contrast, right field targets triggered P300 waves of about the same amplitude over the two hemispheres. The overall amplitude of the P300 to simultaneous bilateral targets was less than the sum of the individual P300 amplitudes produced in response to the unilateral right and left field targets. These shifts in P300 laterality argue against the view that the P300 is an index of diffuse arousal or activation that is triggered in both hemispheres simultaneously irrespective of which hemisphere processes the target information. The results further demonstrate that the P300 does not depend for its production on interhemispheric comparisons of information mediated by the corpus callosum, as suggested recently by Knight et al. (1989).


2007 ◽  
Vol 105 (2) ◽  
pp. 587-608 ◽  
Author(s):  
Metehan Çiçek ◽  
Ereian Nalçaci ◽  
Canan Kalaycioğlu

The aim of this study was to investigate the dynamic nature of the cortical visuospatial attention processes during the line bisection test, which is sensitive to perceptual asymmetries. EEGs of 26 normal volunteers were recorded during the administration of a computerized line bisection test, which requires participants mark the midline of lines using a mouse. Two event-related potentials subsequent and time locked to the line presentations, namely, P300 and a positive slow wave, were obtained. Findings suggested that both potentials were related to the test performance, and the right hemisphere was more active. Analysis suggested a right parietotemporal and superior parietal locus for the P300 and right prefrontal activity for the positive slow wave. A dynamic asymmetrical activity was identified, such that after primary visual perception, spatial processing is then initiated in the right parietotemporal cortex and then proceeds to the right prefrontal cortex.


2021 ◽  
Vol 11 (1) ◽  
pp. 48
Author(s):  
John Stein

(1) Background—the magnocellular hypothesis proposes that impaired development of the visual timing systems in the brain that are mediated by magnocellular (M-) neurons is a major cause of dyslexia. Their function can now be assessed quite easily by analysing averaged visually evoked event-related potentials (VERPs) in the electroencephalogram (EEG). Such analysis might provide a useful, objective biomarker for diagnosing developmental dyslexia. (2) Methods—in adult dyslexics and normally reading controls, we recorded steady state VERPs, and their frequency content was computed using the fast Fourier transform. The visual stimulus was a black and white checker board whose checks reversed contrast every 100 ms. M- cells respond to this stimulus mainly at 10 Hz, whereas parvocells (P-) do so at 5 Hz. Left and right visual hemifields were stimulated separately in some subjects to see if there were latency differences between the M- inputs to the right vs. left hemispheres, and these were compared with the subjects’ handedness. (3) Results—Controls demonstrated a larger 10 Hz than 5 Hz fundamental peak in the spectra, whereas the dyslexics showed the reverse pattern. The ratio of subjects’ 10/5 Hz amplitudes predicted their reading ability. The latency of the 10 Hz peak was shorter during left than during right hemifield stimulation, and shorter in controls than in dyslexics. The latter correlated weakly with their handedness. (4) Conclusion—Steady state visual ERPs may conveniently be used to identify developmental dyslexia. However, due to the limited numbers of subjects in each sub-study, these results need confirmation.


2002 ◽  
Vol 13 (01) ◽  
pp. 001-013 ◽  
Author(s):  
James Jerger ◽  
Rebecca Estes

We studied auditory evoked responses to the apparent movement of a burst of noise in the horizontal plane. Event-related potentials (ERPs) were measured in three groups of participants: children in the age range from 9 to 12 years, young adults in the age range from 18 to 34 years, and seniors in the age range from 65 to 80 years. The topographic distribution of grand-averaged ERP activity was substantially greater over the right hemisphere in children and seniors but slightly greater over the left hemisphere in young adults. This finding may be related to age-related differences in the extent to which judgments of sound movement are based on displacement versus velocity information.


2009 ◽  
Vol 24 (S1) ◽  
pp. 1-1
Author(s):  
T. Sumiyoshi ◽  
Y. Higuchi ◽  
T. Itoh ◽  
M. Matsui ◽  
H. Arai ◽  
...  

The purpose of this study was to determine if perospirone, a second generation antipsychotic drug and partial agonist at serotonin-5-HT1A receptors, enhances electrophysiological activity, such as event-related potentials (ERPs), in frontal brain regions, as well as cognitive function in subjects with schizophrenia. P300 current source images were obtained by means of standardized low resolution brain electromagnetic tomography (sLORETA) before and after treatment with perospirone for 6 months. Perospirone significantly increased P300 current source density in the left superior frontal gyrus, and improved positive symptoms and performance on the script tasks, a measure of verbal social cognition. Perospirone also tended to enhance verbal learning memory in patients with schizophrenia. There was a significant correlation between the changes in P300 amplitudes on the left frontal lead and those in social cognition. These results suggest the changes in three-dimensional distribution of cortical activity, as demonstrated by sLORETA, may mediate some of the actions of antipsychotic drugs. the distinct cognition-enhancing profile of perospirone may be related to its actions on 5-HT1A receptors.


2005 ◽  
Vol 19 (3) ◽  
pp. 204-215 ◽  
Author(s):  
Thierry Baccino ◽  
Yves Manunta

Abstract. This paper presents a new methodology for studying cognition, which combines eye movements (EM) and event-related potentials (ERP) to track the cognitive processes that occur during a single eye fixation. This technique, called eye-fixation-related potentials (EFRP), has the advantage of coupling accurate time measures from ERPs and the location of the eye on the stimulus, so it can be used to disentangle perceptual/attentional/cognitive factors affecting reading. We tested this new technique to describe the controversial parafoveal-on-foveal effects on reading, which concern the question of whether two consecutive words are processed in parallel or sequentially. The experiment directly addressed this question by looking at whether semantic relatedness on a target word in a reading-like situation might affect the processing of a prime word. Three pair-word conditions were tested: A semantically associated target word (horse-mare), a semantically nonassociated target word (horse-table) and a nonword (horse-twsui); EFRPs were compared for all conditions. The results revealed that early ERP components differentiated word and nonword processing within 119 ms postfixation (N1 component). Moreover, the amplitude of the right centrofrontal P140 varied as a function of word type, being larger in response to nonassociated words than to nonwords. This component might index a spatial attention shift to the target word and its visual categorization, being highly sensitive to orthographic regularity and “ill-formedness” of words. The P2 consecutive component (peaking at 215 ms) differentiated associated words and nonassociated words, which can account for the semantic parafoveal effect. The EFRP technique, therefore, appears to be fruitful for establishing a time-line of early cognitive processes during reading.


2019 ◽  
Author(s):  
Rémy Masson ◽  
Yohana Lévêque ◽  
Geneviève Demarquay ◽  
Hesham ElShafei ◽  
Lesly Fornoni ◽  
...  

AbstractObjectivesTo evaluate alterations of top-down and/or bottom-up attention in migraine and their cortical underpinnings.Methods19 migraineurs between attacks and 19 matched control participants performed a task evaluating jointly top-down and bottom-up attention, using visually-cued target sounds and unexpected task-irrelevant distracting sounds. Behavioral responses and MEG/EEG were recorded. Event-related potentials and fields (ERPs/ERFs) were processed and source reconstruction was applied to ERFs.ResultsAt the behavioral level, neither top-down nor bottom-up attentional processes appeared to be altered in migraine. However, migraineurs presented heightened evoked responses following distracting sounds (orienting component of the N1 and Re-Orienting Negativity, RON) and following target sounds (orienting component of the N1), concomitant to an increased recruitment of the right temporo-parietal junction. They also displayed an increased effect of the cue informational value on target processing resulting in the elicitation of a negative difference (Nd).ConclusionsMigraineurs appear to display increased bottom-up orienting response to all incoming sounds, and an enhanced recruitment of top-down attention.SignificanceThe interictal state in migraine is characterized by an exacerbation of the orienting response to attended and unattended sounds. These attentional alterations might participate to the peculiar vulnerability of the migraine brain to all incoming stimuli.HighlightsMigraineurs performed as well as healthy participants in an attention task.However, EEG markers of both bottom-up and top-down attention are increased.Migraine is also associated with a facilitated recruitment of the right temporo-parietal junction.


2016 ◽  
Vol 113 (52) ◽  
pp. E8492-E8501 ◽  
Author(s):  
Roland G. Benoit ◽  
Daniel J. Davies ◽  
Michael C. Anderson

Imagining future events conveys adaptive benefits, yet recurrent simulations of feared situations may help to maintain anxiety. In two studies, we tested the hypothesis that people can attenuate future fears by suppressing anticipatory simulations of dreaded events. Participants repeatedly imagined upsetting episodes that they feared might happen to them and suppressed imaginings of other such events. Suppressing imagination engaged the right dorsolateral prefrontal cortex, which modulated activation in the hippocampus and in the ventromedial prefrontal cortex (vmPFC). Consistent with the role of the vmPFC in providing access to details that are typical for an event, stronger inhibition of this region was associated with greater forgetting of such details. Suppression further hindered participants’ ability to later freely envision suppressed episodes. Critically, it also reduced feelings of apprehensiveness about the feared scenario, and individuals who were particularly successful at down-regulating fears were also less trait-anxious. Attenuating apprehensiveness by suppressing simulations of feared events may thus be an effective coping strategy, suggesting that a deficiency in this mechanism could contribute to the development of anxiety.


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