Functional Anatomy of Perceptual and Semantic Processing for Odors

1999 ◽  
Vol 11 (1) ◽  
pp. 94-109 ◽  
Author(s):  
Jean-P. Royet ◽  
Olivier Koenig ◽  
Marie-C. Gregoire ◽  
Luc Cinotti ◽  
Frank Lavenne ◽  
...  

The functional anatomy of perceptual and semantic processings for odors was studied using positron emission tomography (PET). The first experiment was a pretest in which 71 normal subjects were asked to rate 185 odorants in terms of intensity, familiarity, hedonicity, and comestibility and to name the odorants. This pretest was necessary to select the most appropriate stimuli for the different cognitive tasks of the second experiment. The second one was a PET experiment in which 15 normal subjects were scanned using the water bolus method to measure regional cerebral blood flow (rCBF) during the performance in three conditions. In the first (perceptual) condition, subjects were asked to judge whether an odor was familiar or not. In the second (semantic) condition, subjects had to decide whether an odor corresponded to a comestible item or not. In the third (detection) condition, subjects had to judge whether the perceived stimulus was made of an odor or was just air. It was hypothetized that the three tasks were hierarchically organized from a superficial detection level to a deep semantic level. Odorants were presented with an air-flow olfactometer, which allowed the stimulations to be synchronized with breathing. Subtraction of activation images obtained between familiarity and control judgments revealed that familiarity judgments were mainly associated with the activity of the right orbito-frontal area, the subcallosal gyrus, the left inferior frontal gyrus, the left superior frontal gyrus, and the anterior cingulate (Brodmann's areas 11, 25, 47, 9, and 32, respectively). The comestibility minus familiarity comparison showed that comestibility judgments selectively activated the primary visual areas. In contrast, a decrease in rCBF was observed in these same visual areas for familiarity judgments and in the orbitofrontal area for comestibility judgments. These results suggest that orbito-frontal and visual regions interact in odor processing in a complementary way, depending on the task requirements.

1996 ◽  
Vol 16 (1) ◽  
pp. 23-33 ◽  
Author(s):  
Norihiro Sadato ◽  
Vicente Ibañez ◽  
Marie-Pierre Deiber ◽  
Gregory Campbell ◽  
Marc Leonardo ◽  
...  

To study the effect of the repetition rate of a simple movement on the distribution and magnitude of neuronal recruitment, we measured regional CBF (rCBF) in eight normal volunteers, using positron emission tomography and 15O-labeled water. An auditory-cued, repetitive flexion movement of the right index finger against the thumb was performed at very slow (0.25 and 0.5 Hz), slow (0.75 and 1 Hz), fast (2 and 2.5 Hz), and very fast (3 and 4 Hz) rates. The increase of rCBF during movement relative to the resting condition was calculated for each pair of movement conditions. Left primary sensorimotor cortex showed no significant activation at the very slow rates. There was a rapid rise of rCBF between the slow and the fast rates, but no further increase at the very fast rates. The right cerebellum showed similar changes. Changes in the left primary sensorimotor cortex and the cerebellum likely reflect the effect of the movement rate. The posterior supplementary motor area (SMA) showed its highest activation at the very slow rates but no significant activation at the very fast rates. Changes correlating with those in the SMA were found in the anterior cingulate gyrus, right prefrontal area, and right thalamus. The decreases in CBF may reflect a progressive change in performance from reactive to predictive.


2008 ◽  
Vol 20 (2) ◽  
pp. 342-355 ◽  
Author(s):  
Tomoyo Morita ◽  
Shoji Itakura ◽  
Daisuke N. Saito ◽  
Satoshi Nakashita ◽  
Tokiko Harada ◽  
...  

Individuals can experience negative emotions (e.g., embarrassment) accompanying self-evaluation immediately after recognizing their own facial image, especially if it deviates strongly from their mental representation of ideals or standards. The aim of this study was to identify the cortical regions involved in self-recognition and self-evaluation along with self-conscious emotions. To increase the range of emotions accompanying self-evaluation, we used facial feedback images chosen from a video recording, some of which deviated significantly from normal images. In total, 19 participants were asked to rate images of their own face (SELF) and those of others (OTHERS) according to how photogenic they appeared to be. After scanning the images, the participants rated how embarrassed they felt upon viewing each face. As the photogenic scores decreased, the embarrassment ratings dramatically increased for the participant's own face compared with those of others. The SELF versus OTHERS contrast significantly increased the activation of the right prefrontal cortex, bilateral insular cortex, anterior cingulate cortex, and bilateral occipital cortex. Within the right prefrontal cortex, activity in the right precentral gyrus reflected the trait of awareness of observable aspects of the self; this provided strong evidence that the right precentral gyrus is specifically involved in self-face recognition. By contrast, activity in the anterior region, which is located in the right middle inferior frontal gyrus, was modulated by the extent of embarrassment. This finding suggests that the right middle inferior frontal gyrus is engaged in self-evaluation preceded by self-face recognition based on the relevance to a standard self.


2020 ◽  
Vol 10 (6) ◽  
pp. 395
Author(s):  
Paola Feraco ◽  
Salvatore Nigro ◽  
Luca Passamonti ◽  
Alessandro Grecucci ◽  
Maria Eugenia Caligiuri ◽  
...  

(1) Background: Recently, a series of clinical neuroimaging studies on fibromyalgia (FM) have shown a reduction in cortical volume and abnormally high glutamate (Glu) and glutamate + glutamine (Glx) levels in regions associated with pain modulation. However, it remains unclear whether the volumetric decreases and increased Glu levels in FM are related each other. We hypothesized that higher Glu levels are related to decreases in cortical thickness (CT) and volume in FM patients. (2) Methods: Twelve females with FM and 12 matched healthy controls participated in a session of combined 3.0 Tesla structural magnetic resonance imaging (MRI) and single-voxel MR spectroscopy focused on the thalami and ventrolateral prefrontal cortices (VLPFC). The thickness of the cortical and subcortical gray matter structures and the Glu/Cr and Glx/Cr ratios were estimated. Statistics included an independent t-test and Spearman’s test. (3) Results: The Glu/Cr ratio of the left VLPFC was negatively related to the CT of the left inferior frontal gyrus (pars opercularis (p = 0.01; r = −0.75) and triangularis (p = 0.01; r = −0.70)). Moreover, the Glx/Cr ratio of the left VLPFC was negatively related to the CT of the left middle anterior cingulate gyrus (p = 0.003; r = −0.81). Significantly lower CTs in FM were detected in subparts of the cingulate gyrus on both sides and in the right inferior occipital gyrus (p < 0.001). (4) Conclusions: Our findings are in line with previous observations that high glutamate levels can be related, in a concentration-dependent manner, to the morphological atrophy described in FM patients.


1997 ◽  
Vol 77 (3) ◽  
pp. 1313-1324 ◽  
Author(s):  
M. Jueptner ◽  
K. M. Stephan ◽  
C. D. Frith ◽  
D. J. Brooks ◽  
R.S.J. Frackowiak ◽  
...  

Jueptner, M., K. M. Stephan, C. D. Frith, D. J. Brooks, R.S.J. Frackowiak, and R. E. Passingham. Anatomy of motor learning. I. Frontal cortex and attention to action. J. Neurophysiol. 77: 1313–1324, 1997. We used positron emission tomography to study new learning and automatic performance in normal volunteers. Subjects learned sequences of eight finger movements by trial and error. In a previous experiment we showed that the prefrontal cortex was activated during new learning but not during automatic performance. The aim of the present experiment was to see what areas could be reactivated if the subjects performed the prelearned sequence but were required to pay attention to what they were doing. Scans were carried out under four conditions. In the first the subjects performed a prelearned sequence of eight key presses; this sequence was learned before scanning and was practiced until it had become overlearned, so that the subjects were able to perform it automatically. In the second condition the subjects learned a new sequence during scanning. In a third condition the subjects performed the prelearned sequence, but they were required to attend to what they were doing; they were instructed to think about the next movement. The fourth condition was a baseline condition. As in the earlier study, the dorsal prefrontal cortex and anterior cingulate area 32 were activated during new learning, but not during automatic performance. The left dorsal prefrontal cortex and the right anterior cingulate cortex were reactivated when subjects paid attention to the performance of the prelearned sequence compared with automatic performance of the same task. It is suggested that the critical feature was that the subjects were required to attend to the preparation of their responses. However, the dorsal prefrontal cortex and the anterior cingulate cortex were activated more when the subjects learned a new sequence than they were when subjects simply paid attention to a prelearned sequence. New learning differs from the attention condition in that the subjects generated moves, monitored the outcomes, and remembered the responses that had been successful. All these are nonroutine operations to which the subjects must attend. Further analysis is needed to specify which are the nonroutine operations that require the involvement of the dorsal prefrontal and anterior cingulate cortex.


1996 ◽  
Vol 26 (1) ◽  
pp. 29-38 ◽  
Author(s):  
P. K. McGuire ◽  
D. A. Silbersweig ◽  
R. M. Murray ◽  
A. S. David ◽  
R. S. J. Frackowiak ◽  
...  

SynopsisThe neural correlates of inner speech and of auditory verbal imagery were examined in normal volunteers, using positron emission tomography (PET). Subjects were shown single words which they used to generate short, stereotyped sentences without speaking. In an inner speech task, sentences were silently articulated, while in an auditory verbal imagery condition, subjects imagined sentences being spoken to them in an another person's voice. Inner speech was associated with increased activity in the left inferior frontal gyrus. Auditory verbal imagery was associated with increases in the same region, and in the left premotor cortex, the supplementary motor area and the left temporal cortex. The data suggest that the silent articulation of sentences involves activity in an area concerned with speech generation, while imagining speech is associated with additional activity in regions associated with speech perception.


Author(s):  
Milena Radoman ◽  
Lynne Lieberman ◽  
Jagan Jimmy ◽  
Stephanie M Gorka

Abstract Temporally unpredictable stimuli influence behavior across species, as previously demonstrated for sequences of simple threats and rewards with fixed or variable onset. Neuroimaging studies have identified a specific frontolimbic circuit that may become engaged during the anticipation of temporally unpredictable threat (U-threat). However, the neural mechanisms underlying processing of temporally unpredictable reward (U-reward) are incompletely understood. It is also unclear whether these processes are mediated by overlapping or distinct neural systems. These knowledge gaps are noteworthy given that disruptions within these neural systems may lead to maladaptive response to uncertainty. Here, using functional magnetic resonance imaging data from a sample of 159 young adults, we showed that anticipation of both U-threat and U-reward elicited activation in the right anterior insula, right ventral anterior nucleus of the thalamus and right inferior frontal gyrus. U-threat also activated the right posterior insula and dorsal anterior cingulate cortex, relative to U-reward. In contrast, U-reward elicited activation in the right fusiform and left middle occipital gyrus, relative to U-threat. Although there is some overlap in the neural circuitry underlying anticipation of U-threat and U-reward, these processes appear to be largely mediated by distinct circuits. Future studies are needed to corroborate and extend these preliminary findings.


2021 ◽  
Author(s):  
Divya Sadana ◽  
Rajnish Kumar Gupta ◽  
S Senthil Kumaran ◽  
Sanjeev Jain ◽  
Jamuna Rajeswaran

Creative individuals and their enigmatic personalities have always been a subject of fascination. The current study explored the neuroanatomical basis of creative personality using voxel-based morphometry. The sample comprised of two groups - Creative (CR) group (professional creative artists) and matched controls with no demonstrated artistic creativity (NC) with 20 participants in each group, in the age range of 20-40 years, right-handed, and had minimum average intelligence (IQ > 90). Participants in CR were selected using the creativity achievement questionnaire, creativity was assessed using the Wallach & Kogan test of creativity, and personality was administered using NEO-FFI. Results indicated significantly higher openness to new experiences in CR which positively correlates with the right middle frontal gyrus. An increased grey matter volume in the inferior frontal gyrus, anterior cingulate gyrus in CR, pointing towards the integration of cognitive and imaginative processes that might be implicated in creative personality.


2021 ◽  
Vol 11 ◽  
Author(s):  
Wanjun Zheng ◽  
Yuanping Tao ◽  
Yuzhen Li ◽  
Hang Ye ◽  
Jun Luo

Revenge is common in our daily lives, and people feel good when engaging in revenge behavior. However, revenge behavior is a complex process and remains somewhat of a puzzle of human behavior. Neuroimaging studies have revealed that revenge behaviors are associated with activation of a neural network containing the anterior cingulate cortex, ventral striatum, inferior frontal gyrus, and dorsolateral prefrontal cortex (DLPFC). Recent brain stimulation research using transcranial direct current stimulation (tDCS) and transcranial magnetic stimulation has shown a causal relationship between brain regions and revenge behaviors, but the findings have been mixed. In the present study, we aimed to study whether stimulation in the DLPFC can change participants’ revenge behavior in conditions where participants’ wealth was taken away in different ways. We adapted the moonlighting game and designed a new paradigm. Our study revealed that revenge behavior increased following activation in the right DLPFC, suggesting that the right DLPFC plays an important role in overriding self-interest and retaliation. In addition, our results revealed that the right DLPFC is crucial in revenge behavior related to the motivation of invasion.


2020 ◽  
Author(s):  
Yangyang Cui ◽  
Huai-Bin Liang ◽  
Qian Zhu ◽  
Zhaoxia Qin ◽  
Yue Hu ◽  
...  

Abstract Background: Somatic symptom disorders (SSDs) are common medical disorders characterized by various biological, social, and psychological pathogenic factors. Little is known about the neural correlations of SSD. Methods: In this study, we evaluated the dysfunction in 45 patients with SSD and in 43 controls by combining the regional homogeneity (ReHo) amplitudes of low-frequency fluctuation (ALFF) methods based on resting-state functional magnetic resonance imaging. Results: Compared to the controls, the patients with SSD exhibited significantly greater ReHo in the right cingulate gyrus and smaller ReHo in the right precuneus, left inferior and temporal gyrus extending to the left middle temporal gyrus and left parahippocampal gyrus, and right pons. The SSD patients showed higher ALFF values in the cingulate gyrus extending to the left medial frontal gyrus, right insula extending to the right inferior frontal gyrus, and left medial frontal gyrus extending to the left anterior cingulate cortex. Conclusions: These dysfunction areas seem to have a particular importance for the occurrence of SSD, which may result in dysfunction in self-relevant processes, emotional processing, multimodal integration, arousal, interoception, and body perception.


2016 ◽  
Vol 30 (3) ◽  
pp. 114-123 ◽  
Author(s):  
Tokiko Harada ◽  
Akiko Hayashi ◽  
Norihiro Sadato ◽  
Tetsuya Iidaka

Abstract. Facial expressions play a significant role in displaying feelings. A person’s facial expression automatically induces a similar emotional feeling in an observer; this phenomenon is known as emotional contagion. However, little is known about the neural mechanisms underlying such emotional responses. We conducted an event-related functional magnetic resonance imaging (fMRI) study to examine the neural substrates involved in automatic responses and emotional feelings induced by movies of another person’s happy and sad facial expressions. The fMRI data revealed observing happiness (vs. sadness) evoked activity in the left anterior cingulate gyrus, which is known to be responsible for positive emotional processing and fear inhibition. Conversely, observing sadness (vs. happiness) increased activity in the right superior temporal sulcus and bilateral inferior parietal lobes, which have been reported to be involved in negative emotional processing and the representation of facial movements. In addition, both expressions evoked activity in the right inferior frontal gyrus. These patterns of activity suggest that the observation of dynamic facial expressions automatically elicited dissociable and partially overlapping responses for happy and sad emotions.


Sign in / Sign up

Export Citation Format

Share Document