scholarly journals Neural correlates of perceiving and interpreting engraved prehistoric patterns as human production: effect of archaeological expertise.

2021 ◽  
Author(s):  
Mathilde Salagnon ◽  
Sandrine Cremona ◽  
Marc Joliot ◽  
Francesco d'Errico ◽  
Emmanuel Mellet
Keyword(s):  
Decision Making ◽  
Visual Processing ◽  
Visual Analysis ◽  
Brain Activity ◽  
Occipital Cortex ◽  
Brain Regions ◽  
Salience Network ◽  
Natural Processes ◽  
And Control ◽  
Lateral Occipital Cortex

It has been suggested that engraved abstract patterns dating from the Middle and Lower Palaeolithic served as means of representation and communication. Identifying the brain regions involved in visual processing of these engravings can provide insights into their function. In this study, brain activity was measured during perception of the earliest known Palaeolithic engraved patterns and compared to natural patterns mimicking human-made engravings. Participants were asked to categorise marks as being intentionally made by humans or due to natural processes (e.g. erosion, root etching). To simulate the putative familiarity of our ancestors with the marks, the responses of expert archaeologists and control participants were compared, allowing characterisation of the effect of previous knowledge on both behaviour and brain activity in perception of the marks. Besides a set of regions common to both groups and involved in visual analysis and decision-making, the experts exhibited greater activity in the inferior part of the lateral occipital cortex, ventral occipitotemporal cortex, and medial thalamic regions. These results are consistent with those reported in visual expertise studies, and confirm the importance of the integrative visual areas in the perception of the earliest abstract engravings. The attribution of a natural rather than human origin to the marks elicited greater activity in the salience network in both groups, reflecting the uncertainty and ambiguity in the perception of, and decision-making for, natural patterns. The activation of the salience network might also be related to the process at work in the attribution of an intention to the marks. The primary visual area was not specifically involved in the visual processing of engravings, which argued against its central role in the emergence of engraving production.

scholarly journals Sensory perception in autism: an fMRI ALE meta-analysis

2020 ◽  
Author(s):  
Nazia Jassim ◽  
Simon Baron-Cohen ◽  
John Suckling
Keyword(s):  
Meta Analysis ◽  
Likelihood Estimation ◽  
Sensory Perception ◽  
Superior Temporal Gyrus ◽  
Occipital Cortex ◽  
Anterior Cingulate ◽  
Future Research ◽  
Precentral Gyrus ◽  
And Control ◽  
Lateral Occipital Cortex

Sensory sensitivities occur in up to 90% of autistic individuals. With the recent inclusion of sensory symptoms in the diagnostic criteria for autism, there is a current need to develop neural hypotheses related to autistic sensory perception. Using activation likelihood estimation (ALE), we meta-analysed 52 task-based fMRI studies investigating differences between autistic (n=891) and control (n=967) participants during non-social sensory perception. During complex perception, autistic groups showed more activity in the secondary somatosensory and occipital cortices, insula, caudate, superior temporal gyrus, and inferior parietal lobule, while control groups showed more activity in the frontal and parietal regions. During basic sensory processing, autistic groups showed hyperactivity in the lateral occipital cortex, primary somatosensory and motor cortices, insula, caudate, and thalamus, while controls showed heightened activity in the precentral gyrus, middle frontal gyrus, precuneus, and anterior cingulate cortex. We conclude that autistic individuals, on average, show distinct engagement of sensory-related brain networks during sensory perception. These findings may help guide future research to focus on relevant neurobiological mechanisms underpinning the autistic experience.

scholarly journals The value of what’s to come: neural mechanisms coupling prediction error and reward anticipation

2019 ◽  
Author(s):  
Kiyohito Iigaya ◽  
Tobias U. Hauser ◽  
Zeb Kurth-Nelson ◽  
John P. O’Doherty ◽  
Peter Dayan ◽  
...  
Keyword(s):  
Decision Making ◽  
Information Seeking ◽  
Brain Activity ◽  
Well Being ◽  
Brain Regions ◽  
Functional Coupling ◽  
Hippocampal Activity ◽  
Neural Underpinnings ◽  
To Come ◽  
Human Participants

Having something to look forward to is a keystone of well-being. Anticipation of a future reward, like an upcoming vacation, can often be more gratifying than the very experience itself. Theories of anticipation have described how it induces behaviors ranging from beneficial information-seeking through to harmful addiction. However, it remains unclear how neural systems compute an attractive value from anticipation, instead of from the reward itself. To address this gap, we administered a decision-making task to human participants that allowed us to analyze brain activity during receipt of information predictive of future pleasant outcomes. Using a computational model of anticipatory value that captures participants’ decisions, we show that an anticipatory value signal is orchestrated by influences from three brain regions. Ventromedial prefrontal cortex (vmPFC) tracks the value of anticipation; dopaminergic midbrain responds to information that enhances anticipation, while sustained hippocampal activity provides a functional coupling between these regions. This coordinating function of the hippocampus is consistent with its known role in episodic future thinking. Our findings shed new light on the neural underpinnings of anticipation’s influence over decision-making, while also unifying a range of phenomena associated with risk and time-delay preference.

scholarly journals Contrasting Cortical Activity Associated with Category Memory and Recognition Memory

1998 ◽  
Vol 5 (6) ◽  
pp. 420-428 ◽  
Author(s):  
Paul J. Reber ◽  
Craig E.L. Stark ◽  
Larry R. Squire
Keyword(s):  
Recognition Memory ◽  
Visual Processing ◽  
Functional Neuroimaging ◽  
Brain Activity ◽  
Recognition Task ◽  
Occipital Cortex ◽  
Fmri Data ◽  
Categorization Task ◽  
Neuroimaging Data ◽  
Familiar Stimuli

We collected functional neuroimaging data while volunteers performed similar categorization and recognition memory tasks. In the categorization task, volunteers first studied a series of 40 dot patterns that were distortions of a nonstudied prototype dot pattern. After a delay, while fMRI data were collected, they categorized 72 novel dot patterns according to whether or not they belonged to the previously studied category. In the recognition task, volunteers first studied five dot patterns eight times each. After a delay, while fMRI data were collected, they judged whether each of 72 dot patterns had been studied earlier. We found strikingly different patterns of brain activity in visual processing areas for the two tasks. During the categorization task, the familiar stimuli were associated with decreased activity in posterior occipital cortex, whereas during the recognition task, the familiar stimuli were associated with increased activity in this area. The findings indicate that these two types of memory have contrasting effects on early visual processing and reinforce the view that declarative and nondeclarative memory operate independently.

scholarly journals Decoding images in the mind’s eye: The temporal dynamics of visual imagery

2019 ◽  
Author(s):  
Sophia M. Shatek ◽  
Tijl Grootswagers ◽  
Amanda K. Robinson ◽  
Thomas A. Carlson
Keyword(s):  
Mental Imagery ◽  
Visual Processing ◽  
Temporal Dynamics ◽  
Brain Activity ◽  
Brain Regions ◽  
Time Resolved ◽  
Santa Claus ◽  
Physical Stimuli ◽  
Multivariate Pattern ◽  
The Mind

AbstractMental imagery is the ability to generate images in the mind in the absence of sensory input. Both perceptual visual processing and internally generated imagery engage large, overlapping networks of brain regions. However, it is unclear whether they are characterized by similar temporal dynamics. Recent magnetoencephalography work has shown that object category information was decodable from brain activity during mental imagery, but the timing was delayed relative to perception. The current study builds on these findings, using electroencephalography to investigate the dynamics of mental imagery. Sixteen participants viewed two images of the Sydney Harbour Bridge and two images of Santa Claus. On each trial, they viewed a sequence of the four images and were asked to imagine one of them, which was cued retroactively by its temporal location in the sequence. Time-resolved multivariate pattern analysis was used to decode the viewed and imagined stimuli. Our results indicate that the dynamics of imagery processes are more variable across, and within, participants compared to perception of physical stimuli. Although category and exemplar information was decodable for viewed stimuli, there were no informative patterns of activity during mental imagery. The current findings suggest stimulus complexity, task design and individual differences may influence the ability to successfully decode imagined images. We discuss the implications of these results for our understanding of the neural processes underlying mental imagery.

scholarly journals Changes in structural network topology correlate with severity of hallucinatory behavior in Parkinson’s disease

2019 ◽  
Vol 3 (2) ◽  
pp. 521-538 ◽  
Author(s):  
Julie M. Hall ◽  
Claire O’Callaghan ◽  
Alana J. Muller ◽  
Kaylena A. Ehgoetz Martens ◽  
Joseph R. Phillips ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Network Topology ◽  
Visual Processing ◽  
Temporal Cortex ◽  
Occipital Cortex ◽  
Structural Network ◽  
Visual Cortices ◽  
Transfer Of Information ◽  
Lateral Occipital Cortex

Inefficient integration between bottom-up visual input and higher order visual processing regions is implicated in visual hallucinations in Parkinson’s disease (PD). Here, we investigated white matter contributions to this perceptual imbalance hypothesis. Twenty-nine PD patients were assessed for hallucinatory behavior. Hallucination severity was correlated to connectivity strength of the network using the network-based statistic approach. The results showed that hallucination severity was associated with reduced connectivity within a subnetwork that included the majority of the diverse club. This network showed overall greater between-module scores compared with nodes not associated with hallucination severity. Reduced between-module connectivity in the lateral occipital cortex, insula, and pars orbitalis and decreased within-module connectivity in the prefrontal, somatosensory, and primary visual cortices were associated with hallucination severity. Conversely, hallucination severity was associated with increased between- and within-module connectivity in the orbitofrontal and temporal cortex, as well as regions comprising the dorsal attentional and default mode network. These results suggest that hallucination severity is associated with marked alterations in structural network topology with changes in participation along the perceptual hierarchy. This may result in the inefficient transfer of information that gives rise to hallucinations in PD.

scholarly journals TMS to the Lateral Occipital Cortex Disrupts Object Processing but Facilitates Scene Processing

2011 ◽  
Vol 23 (12) ◽  
pp. 4174-4184 ◽  
Author(s):  
Caitlin R. Mullin ◽  
Jennifer K. E. Steeves
Keyword(s):  
Temporal Dynamics ◽  
Scene Perception ◽  
Visual Image ◽  
Object Perception ◽  
Occipital Cortex ◽  
Brain Regions ◽  
Object Processing ◽  
Repetitive Tms ◽  
Scene Processing ◽  
Lateral Occipital Cortex

The study of brain-damaged patients and advancements in neuroimaging have lead to the discovery of discrete brain regions that process visual image categories, such as objects and scenes. However, how these visual image categories interact remains unclear. For example, is scene perception simply an extension of object perception, or can global scene “gist” be processed independently of its component objects? Specifically, when recognizing a scene such as an “office,” does one need to first recognize its individual objects, such as the desk, chair, lamp, pens, and paper to build up the representation of an “office” scene? Here, we show that temporary interruption of object processing through repetitive TMS to the left lateral occipital cortex (LO), an area known to selectively process objects, impairs object categorization but surprisingly facilitates scene categorization. This result was replicated in a second experiment, which assessed the temporal dynamics of this disruption and facilitation. We further showed that repetitive TMS to left LO significantly disrupted object processing but facilitated scene processing when stimulation was administered during the first 180 msec of the task. This demonstrates that the visual system retains the ability to process scenes during disruption to object processing. Moreover, the facilitation of scene processing indicates disinhibition of areas involved in global scene processing, likely caused by disrupting inhibitory contributions from the LO. These findings indicate separate but interactive pathways for object and scene processing and further reveal a network of inhibitory connections between these visual brain regions.

scholarly journals Local sleep homeostasis in the avian brain: convergence of sleep function in mammals and birds?

2011 ◽  
Vol 278 (1717) ◽  
pp. 2419-2428 ◽  
Author(s):  
John A. Lesku ◽  
Alexei L. Vyssotski ◽  
Dolores Martinez-Gonzalez ◽  
Christiane Wilzeck ◽  
Niels C. Rattenborg
Keyword(s):  
Slow Wave ◽  
Rem Sleep ◽  
Visual Processing ◽  
Slow Wave Sleep ◽  
Brain Activity ◽  
Brain Regions ◽  
Avian Brain ◽  
Brain Functioning ◽  
Sleep Homeostasis ◽  
Local Sleep

The function of the brain activity that defines slow wave sleep (SWS) and rapid eye movement (REM) sleep in mammals is unknown. During SWS, the level of electroencephalogram slow wave activity (SWA or 0.5–4.5 Hz power density) increases and decreases as a function of prior time spent awake and asleep, respectively. Such dynamics occur in response to waking brain use, as SWA increases locally in brain regions used more extensively during prior wakefulness. Thus, SWA is thought to reflect homeostatically regulated processes potentially tied to maintaining optimal brain functioning. Interestingly, birds also engage in SWS and REM sleep, a similarity that arose via convergent evolution, as sleeping reptiles and amphibians do not show similar brain activity. Although birds deprived of sleep show global increases in SWA during subsequent sleep, it is unclear whether avian sleep is likewise regulated locally. Here, we provide, to our knowledge, the first electrophysiological evidence for local sleep homeostasis in the avian brain. After staying awake watching David Attenborough's The Life of Birds with only one eye, SWA and the slope of slow waves (a purported marker of synaptic strength) increased only in the hyperpallium—a primary visual processing region—neurologically connected to the stimulated eye. Asymmetries were specific to the hyperpallium, as the non-visual mesopallium showed a symmetric increase in SWA and wave slope. Thus, hypotheses for the function of mammalian SWS that rely on local sleep homeostasis may apply also to birds.

The Effects of Presentation Rate During Word and Pseudoword Reading: A Comparison of PET and fMRI

2000 ◽  
Vol 12 (supplement 2) ◽  
pp. 145-156 ◽  
Author(s):  
Andrea Mechelli ◽  
Karl J. Friston ◽  
Cathy J. Price
Keyword(s):  
Visual Processing ◽  
Word Processing ◽  
Brain Activity ◽  
Presentation Rate ◽  
Word Type ◽  
Brain Regions ◽  
Design Parameters ◽  
Specific Rate ◽  
Precentral Gyrus ◽  
Stimulus Rate

The effect of stimulus rate and its interaction with stimulus type on brain activity during reading was investigated using functional magnetic resonance imaging (fMRI). This (i) enabled the segregation of brain regions showing differential responses, (ii) identified the optimum experimental design parameters for maximizing sensitivity, and (iii) allowed us to evaluate further the sources of discrepancy between positron emission tomography (PET) and fMRI signals. The effect of visual word rate has already been investigated in a previous PET study. However, rate effects can be very different in PET and fMRI, as seen in previous studies of auditory word processing. In this work, we attempt to replicate rate-sensitive activations observed with PET using fMRI. Our objective was to characterize the discrepancies in regionally specific rate-sensitive effects between the two imaging modalities. Subjects were presented with words and pseudowords at varying rates while performing a silent reading task. The analysis specifically identified regions showing (i) an effect of stimulus rate on brain activity during reading; (ii) modulation of this effect by word type; and (iii) increased activity during reading relative to rest, but with no dependence on stimulus rate. The results identified similar effects of rate for words and pseudowords (no interactions between rate and word type reached significance). Irrespective of word type, strong positive linear effects of rate (i.e., activity increasing with rate) were detected in visual areas, right superior temporal gyrus, and bilateral precentral gyrus. These findings replicate the results of the previous PET study, confirming that activation in regions associated with visual processing and response generation increases with the number of stimuli. Likewise, we detected rate-independent effects reported in the previous PET study in bilateral anterior middle temporal, inferior frontal, and superior parietal regions. These results differentiate the functionally specific responses in rate-dependent and rate-independent areas. However, for negative effects of rate, fMRI did not replicate the effects seen in PET, suggesting some form of hemodynamic “rectification.” The discussion focuses on differences between evoked rCBF and BOLD signals.

scholarly journals Neuronal Correlates of Small Animal Phobia in Human Subjects through fMRI: The Role of the Number and Proximity of Stimuli

Life ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 275
Author(s):  
Ascensión Fumero ◽  
Rosario J. Marrero ◽  
Francisco Rivero ◽  
Yolanda Alvarez-Pérez ◽  
Juan Manuel Bethencourt ◽  
...  
Keyword(s):  
Human Subjects ◽  
Brain Activity ◽  
Small Animal ◽  
Occipital Cortex ◽  
Brain Regions ◽  
Precentral Gyrus ◽  
Key Factors ◽  
Sensory Activity ◽  
Emotion Regulation Strategy ◽  
Phobic Stimuli

Brain regions involved in small-animal phobia include subcortical and cortical areas. The present study explored the neuronal correlates of small-animal phobia through fMRI data to determine whether a manipulation of number and proximity parameters affects the neurobiology of the processing of feared stimuli. The participants were 40 individuals with phobia and 40 individuals without phobia (28.7% male and 71.3% female). They watched videos of real and virtual images of spiders, cockroaches and lizards in motion presented more or less nearby with one or three stimuli in the different conditions. The results suggested a differential brain activity between participants with and without phobia depending on the proximity and number of phobic stimuli. Proximity activated the motor response marked by the precentral gyrus and the cingulate gyrus. By contrast, the number of stimuli was associated with significant sensory activity in the postcentral gyrus and ventromedial prefrontal cortex. We also observed a greater activity in the occipital cortex when exploring the number compared to the proximity factor. Threatening stimuli presented nearby and those presented in greater numbers generated an intense phobic response, suggesting a different emotion regulation strategy. Based on these findings, exposure therapies might consider including proximity to the threat and number of stimuli as key factors in treatment.

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