Quantitative Analysis of Attention and Detection Signals During Visual Search

2003 ◽  
Vol 90 (5) ◽  
pp. 3384-3397 ◽  
Author(s):  
Gordon L. Shulman ◽  
Mark P. McAvoy ◽  
Melanie C. Cowan ◽  
Serguei V. Astafiev ◽  
Aaron P. Tansy ◽  
...  
Keyword(s):  
Large Fraction ◽  
Additive Model ◽  
Decision Criterion ◽  
Blood Oxygenation ◽  
Anterior Cingulate ◽  
Frontal Eye Field ◽  
Temporoparietal Junction ◽  
Flow Models ◽  
Dependent Signal ◽  
Cortical Regions

Prior work has distinguished regions in the intraparietal sulcus (IPs) and frontal eye field (FEF) involved in the voluntary control of attention, from more ventral regions in the temporoparietal junction (TPJ) involved in target detection. The present results show that when subjects search for and detect a visual target stimulus among nontargets, these regions show sensory-, search-, and detection-related signals that both confirm and refine these functional distinctions. The different signals were isolated by an additive model that accounted for a large fraction of BOLD (blood oxygenation level-dependent) signal modulation over the brain. Both IPs and FEF were activated during search through nontargets, consistent with a role in maintaining attention-related signals during search. However, unlike FEF, IPs also showed stimulus-related activations, and may combine signals related to sensory and task-dependent components of salience. Although IPs-FEF showed search-related activations, the TPJ was deactivated during search. TPJ activations were confined to detection-related signals. These results provide a much stronger dissociation between the TPJ and IPs-FEF than previous work, while indicating functional differences between frontal and parietal regions that are often coactivated in studies of attention. Finally, continuous flow models of information processing predict that during search, signals from missed targets should be fed from sensory to associative regions rather than being gated by the decision criterion. Correspondingly, missed targets significantly activated parietal (e.g., right TPJ) and frontal (e.g., anterior insula, anterior cingulate) regions, although with a smaller magnitude than detected targets. Surprisingly, many cortical regions showed equivalent signals from detected targets and the completion of target-absent trials, reflecting a widespread signal unrelated to motor execution.

Psychology of attention

2012 ◽  
pp. 245-249
Author(s):  
Elizabeth Coulthard ◽  
Masud Husain
Keyword(s):  
Human Brain ◽  
Parietal Lobe ◽  
Inferior Frontal Gyrus ◽  
Good Deal ◽  
Anterior Cingulate ◽  
Frontal Eye Field ◽  
Temporoparietal Junction ◽  
Flexible Control ◽  
Eye Field ◽  
Brain Processing

Attention is generally taken to be the process by which people are able to concentrate on certain information or processes, while ignoring other events. It appears to be a fundamental attribute of human brain processing, although difficult to pin down in terms of mechanism. Psychologists have attempted to fractionate attention in many different ways, using ingenious behavioural paradigms. In this section we, too, will consider different aspects of attention: selective, phasic and sustained, divided and executive control of attention. However, it would be fair to say that all these aspects of attention do not normally operate in isolation. Instead they interact, and deficiencies in one aspect of attention, for example, in a patient population, often to do not occur in isolation. Functional imaging and lesion studies of attention have proliferated in recent years, attempting to place a neurobiological framework to these varied processes. In general, these studies also tend to confirm the view that attention is likely an emergent property of widespread brain networks, with a special emphasis on frontal and parietal regions of the human brain (Fig. 2.5.2.1). In this discussion we illustrate several aspects of attention with examples particularly from literature on visual attention, which is the most widely studied area, but it should be appreciated that many of the concepts discussed here extend to other domains. In fact, there is a good deal of evidence to suggest that several aspects of attention operate at a supra- or cross-modal level allowing integration of information from different sources. Recent studies suggest there are two fronto-parietal networks: (Fig. 2.5.2.1) a dorsal parieto-frontal network involving the superior parietal lobe (SPL) and dorsal frontal regions such as the frontal eye field (FEF); and a ventral network involving the inferior parietal lobe (IPL), temporoparietal junction (TPJ) and inferior frontal gyrus (IFG). In addition, dorsomedial frontal areas, including the anterior cingulate cortex (ACC) and pre-supplementary area (pre-SMA) may play a key role in flexible control of attention for strategic behaviour.

Representation of Umami Taste in the Human Brain

2003 ◽  
Vol 90 (1) ◽  
pp. 313-319 ◽  
Author(s):  
I.E.T. de Araujo ◽  
M. L. Kringelbach ◽  
E. T. Rolls ◽  
P. Hobden
Keyword(s):  
Orbitofrontal Cortex ◽  
Anterior Part ◽  
Monosodium Glutamate ◽  
Blood Oxygenation ◽  
Anterior Cingulate ◽  
Bold Signal ◽  
Taste System ◽  
Umami Taste ◽  
Oxygenation Level ◽  
Cortical Regions

Umami taste stimuli, of which an exemplar is monosodium glutamate (MSG) and which capture what is described as the taste of protein, were shown using functional MRI (fMRI) to activate similar cortical regions of the human taste system to those activated by a prototypical taste stimulus, glucose. These taste regions included the insular/opercular cortex and the caudolateral orbitofrontal cortex. A part of the rostral anterior cingulate cortex (ACC) was also activated. When the nucleotide 0.005 M inosine 5′-monophosphate (IMP) was added to MSG (0.05 M), the blood oxygenation-level dependent (BOLD) signal in an anterior part of the orbitofrontal cortex showed supralinear additivity; this may reflect the subjective enhancement of umami taste that has been described when IMP is added to MSG. These results extend to humans previous studies in macaques showing that single neurons in these taste cortical areas can be tuned to umami stimuli.

Multisensory Cortical Signal Increases and Decreases During Vestibular Galvanic Stimulation (fMRI)

2001 ◽  
Vol 85 (2) ◽  
pp. 886-899 ◽  
Author(s):  
Sandra Bense ◽  
Thomas Stephan ◽  
Tarek A. Yousry ◽  
Thomas Brandt ◽  
Marianne Dieterich
Keyword(s):  
Blood Oxygenation ◽  
Anterior Cingulate ◽  
Middle Temporal Gyrus ◽  
Frontal Eye Field ◽  
Single Subject ◽  
Precentral Gyrus ◽  
Bold Signal ◽  
Ocular Motor ◽  
Vestibular Cortex ◽  
Middle Temporal

Functional magnetic resonance imaging blood-oxygenation-level-dependent (BOLD) signal increases (activations) and BOLD signal decreases (“deactivations”) were compared in six healthy volunteers during galvanic vestibular (mastoid) and galvanic cutaneous (neck) stimulation in order to differentiate vestibular from ocular motor and nociceptive functions. By calculating the contrast for vestibular activation minus cutaneous activation for the group, we found activations in the anterior parts of the insula, the paramedian and dorsolateral thalamus, the putamen, the inferior parietal lobule [Brodmann area (BA) 40], the precentral gyrus (frontal eye field, BA 6), the middle frontal gyrus (prefrontal cortex, BA 46/9), the middle temporal gyrus (BA 37), the superior temporal gyrus (BA 22), and the anterior cingulate gyrus (BA 32) as well as in both cerebellar hemispheres. These activations can be attributed to multisensory vestibular and ocular motor functions. Single-subject analysis in addition showed distinctly nonoverlapping activations in the posterior insula, which corresponds to the parieto-insular vestibular cortex in the monkey. During vestibular stimulation, there was also a significant signal decrease in the visual cortex (BA 18, 19), which spared BA 17. A different “deactivation” was found during cutaneous stimulation; it included upper parieto-occipital areas in the middle temporal and occipital gyri (BA 19/39/18). Under both stimulation conditions, there were signal decreases in the somatosensory cortex (BA 2/3/4). Stimulus-dependent, inhibitory vestibular-visual, and nociceptive-somatosensory interactions may be functionally significant for processing perception and sensorimotor control.

Central Nervous System Processing of Emotions in Children with Fecal Incontinence and Constipation

2019 ◽  
Vol 47 (1) ◽  
pp. 67-71
Author(s):  
Monika Equit ◽  
Justine Niemczyk ◽  
Anna Kluth ◽  
Carla Thomas ◽  
Mathias Rubly ◽  
...  
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Fecal Incontinence ◽  
Event Related Potentials ◽  
Anterior Cingulate ◽  
Afferent Pathways ◽  
Study Results ◽  
Related Potentials ◽  
The Central Nervous System ◽  
Cortical Regions

Abstract. Objective: Fecal incontinence and constipation are common disorders in childhood. The enteric nervous system and the central nervous system are highly interactive along the brain-gut axis. The interaction is mainly afferent. These afferent pathways include centers that are involved in the central nervous processing of emotions as the mid/posterior insula and the anterior cingulate cortex. A previous study revealed altered processing of emotions in children with fecal incontinence. The present study replicates these results. Methods: In order to analyze the processing of emotions, we compared the event-related potentials of 25 children with fecal incontinence and constipation to those of 15 control children during the presentation of positive, negative, and neutral pictures. Results: Children with fecal incontinence and constipation showed altered processing of emotions, especially in the parietal and central cortical regions. Conclusions: The main study results of the previous study were replicated, increasing the certainty and validity of the findings.

scholarly journals The Role of Primate Prefrontal Cortex in Bias and Shift Between Visual Dimensions

2019 ◽  
Vol 30 (1) ◽  
pp. 85-99 ◽  
Author(s):  
Farshad A Mansouri ◽  
Mark J Buckley ◽  
Daniel J Fehring ◽  
Keiji Tanaka
Keyword(s):  
Prefrontal Cortex ◽  
Anterior Cingulate ◽  
Top Down ◽  
Attentional Processes ◽  
Prefrontal Cortical ◽  
Frontopolar Cortex ◽  
Dorsolateral Prefrontal ◽  
Cortical Regions ◽  
Visual Cortical ◽  
Bilateral Lesions

Abstract Imaging and neural activity recording studies have shown activation in the primate prefrontal cortex when shifting attention between visual dimensions is necessary to achieve goals. A fundamental unanswered question is whether representations of these dimensions emerge from top-down attentional processes mediated by prefrontal regions or from bottom-up processes within visual cortical regions. We hypothesized a causative link between prefrontal cortical regions and dimension-based behavior. In large cohorts of humans and macaque monkeys, performing the same attention shifting task, we found that both species successfully shifted between visual dimensions, but both species also showed a significant behavioral advantage/bias to a particular dimension; however, these biases were in opposite directions in humans (bias to color) versus monkeys (bias to shape). Monkeys’ bias remained after selective bilateral lesions within the anterior cingulate cortex (ACC), frontopolar cortex, dorsolateral prefrontal cortex (DLPFC), orbitofrontal cortex (OFC), or superior, lateral prefrontal cortex. However, lesions within certain regions (ACC, DLPFC, or OFC) impaired monkeys’ ability to shift between these dimensions. We conclude that goal-directed processing of a particular dimension for the executive control of behavior depends on the integrity of prefrontal cortex; however, representation of competing dimensions and bias toward them does not depend on top-down prefrontal-mediated processes.

scholarly journals Roles of Ventromedial Prefrontal Cortex and Anterior Cingulate in Subjective Valuation of Prospective Effort

2018 ◽  
Vol 29 (10) ◽  
pp. 4277-4290 ◽  
Author(s):  
Patrick S Hogan ◽  
Joseph K Galaro ◽  
Vikram S Chib
Keyword(s):  
Decision Making ◽  
Prefrontal Cortex ◽  
Brain Activity ◽  
Blood Oxygenation ◽  
Ventromedial Prefrontal Cortex ◽  
Anterior Cingulate ◽  
Effort Level ◽  
Perceived Effort ◽  
Trade Offs ◽  
Subjective Valuation

Abstract The perceived effort level of an action shapes everyday decisions. Despite the importance of these perceptions for decision-making, the behavioral and neural representations of the subjective cost of effort are not well understood. While a number of studies have implicated anterior cingulate cortex (ACC) in decisions about effort/reward trade-offs, none have experimentally isolated effort valuation from reward and choice difficulty, a function that is commonly ascribed to this region. We used functional magnetic resonance imaging to monitor brain activity while human participants engaged in uncertain choices for prospective physical effort. Our task was designed to examine effort-based decision-making in the absence of reward and separated from choice difficulty—allowing us to investigate the brain’s role in effort valuation, independent of these other factors. Participants exhibited subjectivity in their decision-making, displaying increased sensitivity to changes in subjective effort as objective effort levels increased. Analysis of blood-oxygenation-level dependent activity revealed that the ventromedial prefrontal cortex (vmPFC) encoded the subjective valuation of prospective effort, and ACC activity was best described by choice difficulty. These results provide insight into the processes responsible for decision-making regarding effort, partly dissociating the roles of vmPFC and ACC in prospective valuation of effort and choice difficulty.

Modulation of the Visual Word Retrieval System in Writing: A Functional MRI Study on the Japanese Orthographies

2002 ◽  
Vol 14 (1) ◽  
pp. 104-115 ◽  
Author(s):  
Kimihiro Nakamura ◽  
Manabu Honda ◽  
Shigeru Hirano ◽  
Tatsuhide Oga ◽  
Nobukatsu Sawamoto ◽  
...  
Keyword(s):  
Retrieval System ◽  
Temporal Cortex ◽  
Visual Word ◽  
Word Retrieval ◽  
Anterior Cingulate ◽  
Input Stimulus ◽  
Semantic Judgment ◽  
Cortical Regions ◽  
Mri Study ◽  
Mental Recall

We used functional magnetic resonance imaging (fMRI) to examine whether the act of writing involves different neuro-psychological mechanisms between the two script systems of the Japanese language: kanji (ideogram) and kana (phonogram). The main experiments employed a 2 × 2 factorial design that comprised writing-to-dictation and visual mental recall for kanji and kana. For both scripts, the actual writing produced a widespread fronto-parietal activation in the left hemisphere. Especially, writing of kanji activated the left posteroinferior temporal cortex (lPITC), whereas that of kana also yielded a trend of activation in the same area. Mental recall for both scripts activated similarly the left parieto-temporal regions including the lPITC. The writing versus mental recall comparison revealed greater activations in the left sensorimotor areas and right cerebellum. The kanji versus kana comparison showed increased responses in the left prefrontal and anterior cingulate areas. Especially, the lPITC showed a significant task-by-script interaction. Two additional control tasks, repetition (REP) and semantic judgment (SJ), activated the bilateral perisylvian areas, but enhanced the lPITC response only weakly. These results suggest that writing of the ideographic and phonographic scripts, although using the largely same cortical regions, each modulates the visual word-retrieval system according to their graphic features. Furthermore, comparisons with two additional tasks indicate that the activity of the lPITC increases especially in expressive language operations regardless of sensory modalities of the input stimulus.

scholarly journals Mental travel in the social domain

2019 ◽  
Author(s):  
Mordechai Hayman ◽  
Shahar Arzy
Keyword(s):  
Social Network ◽  
Anterior Cingulate Cortex ◽  
Brain Activity ◽  
Cingulate Cortex ◽  
Retrosplenial Cortex ◽  
Anterior Cingulate ◽  
Significant Other ◽  
Temporoparietal Junction ◽  
The Social ◽  
Famous Person

“Mental travel” is the ability to imagine oneself in different places and times and to adopt other people’s point of view (POV), also termed “Theory of Mind (ToM)”. While ToM has been extensively investigated, self-projection with respect to ones’ own and others’ social networks has yet to be systematically studied.Here we asked participants to “project” themselves to four different POVs: a significant other, a non-significant other, a famous-person, and their own-self. From each POV they were asked to rate the level of affiliation (closeness) to different individuals in the respective social network while undergoing functional MRI.Participants were always faster making judgments from their own POV compared to other POVs (self-projection effect) and for people who were personally closer to their adopted POV (self-reference effect). Brain activity at the medial prefrontal and anterior cingulate cortex in the self POV condition was found to be higher compared to all other conditions. Activity at the right temporoparietal junction and medial parietal cortex was found to distinguish between the personally related (self, significant- and non-significant others) and unrelated (famous-person) individuals within the social network. Regardless of the POV, the precuneus, anterior cingulate cortex, prefrontal cortex, and temporoparietal junction distinguished between relatively closer and distant people. Representational similarity analysis (RSA) implicated the left retrosplenial cortex as crucial for social distance processing across all POVs.

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