In comparative visual cognition research, the influence of information acquired by nonvisual senses has received little attention. Systematic studies focusing on how the integration of information ...from sight and touch can affect animal perception are sparse. Here, we investigated whether tactile input improves visual discrimination ability of a bird, the kea, and capuchin monkeys, two species with acute vision, and known for their tendency to handle objects. To this end, we assessed whether, at the attainment of a criterion, accuracy and/or learning speed in the visual modality were enhanced by haptic (i.e. active tactile) exploration of an object. Subjects were trained to select the positive stimulus between two cylinders of the same shape and size, but with different surface structures. In the Sight condition, one pair of cylinders was inserted into transparent Plexiglas tubes. This prevented animals from haptically perceiving the objects' surfaces. In the Sight and Touch condition, one pair of cylinders was not inserted into transparent Plexiglas tubes. This allowed the subjects to perceive the objects' surfaces both visually and haptically. We found that both kea and capuchins (1) showed comparable levels of accuracy at the attainment of the learning criterion in both conditions, but (2) required fewer trials to achieve the criterion in the Sight and Touch condition. Moreover, this study showed that both kea and capuchins can integrate information acquired by the visual and tactile modalities. To our knowledge, this represents the first evidence of visuotactile integration in a bird species. Overall, our findings demonstrate that the acquisition of tactile information while manipulating objects facilitates visual discrimination of objects in two phylogenetically distant species.
•We tested the role of visuotactile integration in an object discrimination task.•Kea and capuchins exploited tactile memory in visual object recognition.•Touch accelerated learning speed for visual object recognition in both species.•Kea and capuchins showed comparable learning abilities to solve the task.
Most experimental paradigms to study visual cognition in humans and non-human species are based on discrimination tasks involving the choice between two or more visual stimuli. To this end, different ...types of stimuli and procedures for stimuli presentation are used, which highlights the necessity to compare data obtained with different methods. The present study assessed whether, and to what extent, capuchin monkeys' ability to solve a size discrimination problem is influenced by the type of procedure used to present the problem. Capuchins' ability to generalise knowledge across different tasks was also evaluated. We trained eight adult tufted capuchin monkeys to select the larger of two stimuli of the same shape and different sizes by using pairs of food items (Experiment 1), computer images (Experiment 1) and objects (Experiment 2). Our results indicated that monkeys achieved the learning criterion faster with food stimuli compared to both images and objects. They also required consistently fewer trials with objects than with images. Moreover, female capuchins had higher levels of acquisition accuracy with food stimuli than with images. Finally, capuchins did not immediately transfer the solution of the problem acquired in one task condition to the other conditions. Overall, these findings suggest that--even in relatively simple visual discrimination problems where a single perceptual dimension (i.e., size) has to be judged--learning speed strongly depends on the mode of presentation.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The dot probe task is an experimental procedure commonly used to study how animals (including humans) pay attention to different stimuli. In this study, we evaluated how different durations of image ...exposure modulate the response to this task and how male and female tufted capuchin monkeys (Sapajus spp.) respond to a dot probe presented immediately after different social stimuli. Subjects were shown pairs of images of unfamiliar conspecifics: a male versus a female or two individuals grooming versus two individuals not engaged in grooming (nongrooming). With shorter image exposures (250ms) both sexes showed shorter response times to the dot probe after presentation of (i.e. biased their attention towards) images of unfamiliar males compared to females, and did not show any bias towards images of grooming compared to nongrooming. With longer image exposures (1000ms) females biased their attention towards images of unfamiliar females, while males did not show any difference; in contrast, males biased their attention towards images of grooming compared to nongrooming, while females did not show any difference. We interpret these results as showing that responses to the dot probe task with different image exposures reflect different attentional phenomena, and that the two sexes differ in how social stimuli affect their attention.
•We assessed attention to social stimuli in capuchin monkeys using a dot probe task.•Stimuli were images of unfamiliar conspecifics shown for 250 or 1000ms.•Both sexes biased their attention towards images of males shown for 250ms.•Females biased their attention towards images of females shown for 1000ms.•Males biased their attention towards images of grooming shown for 1000ms.
•The influence of touch on visual object recognition was evaluated in capuchin monkeys.•Capuchins discriminated objects differing in size, shape or surface structure.•Capuchins had to visually select ...objects with and without additional tactile cues.•Tactile cues accelerated capuchins’ learning speed for visual object discrimination.
Primates perceive many object features through vision and touch. To date, little is known on how the synergy of these two sensory modalities contributes to enhance object recognition. Here, we investigated in capuchin monkeys (N = 12) whether manipulating objects and retaining tactile information enhanced visual recognition of geometrical object properties on different scales. Capuchins were trained to visually select the rewarded one of two objects differing in size, shape (larger-scale) or surface structure (smaller-scale). Objects were explored in two experimental conditions: the Sight condition prevented capuchins from touching the chosen object; the Sight and Touch condition allowed them to touch the selected object. Our results indicated that tactile information increased the capuchins’ learning speed for visual discrimination of object features. Moreover, the capuchins’ learning speed was higher in both size and shape discrimination compared to surface discrimination regardless of the availability of tactile input. Overall, our data demonstrated that the acquisition of tactile information about object features was advantageous for the capuchins and allowed them to achieve high levels of visual accuracy faster. This suggests that information from touch potentiated object recognition in the visual modality.
In the last two decades, comparative research has addressed the issue of how the global and local levels of structure of visual stimuli are processed by different species, using Navon-type ...hierarchical figures, i.e. smaller local elements that form larger global configurations. Determining whether or not the variety of procedures adopted to test different species with hierarchical figures are equivalent is of crucial importance to ensure comparability of results. Among non-human species, global/local processing has been extensively studied in tufted capuchin monkeys using matching-to-sample tasks with hierarchical patterns. Local dominance has emerged consistently in these New World primates. In the present study, we assessed capuchins’ processing of hierarchical stimuli with a method frequently adopted in studies of global/local processing in non-primate species: the conflict–choice task. Different from the matching-to-sample procedure, this task involved processing local and global information retained in long-term memory. Capuchins were trained to discriminate between consistent hierarchical stimuli (similar global and local shape) and then tested with inconsistent hierarchical stimuli (different global and local shapes). We found that capuchins preferred the hierarchical stimuli featuring the correct local elements rather than those with the correct global configuration. This finding confirms that capuchins’ local dominance, typically observed using matching-to-sample procedures, is also expressed as a local preference in the conflict–choice task. Our study adds to the growing body of comparative studies on visual grouping functions by demonstrating that the methods most frequently used in the literature on global/local processing produce analogous results irrespective of extent of the involvement of memory processes.
Since its emergence, SARS-CoV-2 Omicron clade has shown a marked degree of variability and different clinical presentation compared with previous clades. Here we demonstrate that at least four ...Omicron lineages circulated in children since December 2021, and studied until November 2022: BA.1 (33.6%), BA.2 (40.6%), BA.5 (23.7%) and BQ.1 (2.1%). At least 70% of infections concerned children under 1 year, most of them being infected with BA.2 lineages (n = 201, 75.6%). Looking at SARS-CoV-2 genetic variability, 69 SNPs were found to be significantly associated in pairs, (phi < - 0.3 or > 0.3 and p-value < 0.001). 16 SNPs were involved in 4 distinct clusters (bootstrap > 0.75). One of these clusters (A23040G, A27259C, T23617G, T23620G) was also positively associated with moderate/severe COVID-19 presentation (AOR 95% CI 2.49 1.26-4.89 p-value: 0.008) together with comorbidities (AOR 95% CI 2.67 1.36-5.24 p-value: 0.004). Overall, these results highlight the extensive SARS-CoV-2 Omicron circulation in children, mostly aged < 1 year, and provide insights on viral diversification even considering low-abundant SNPs, finally suggesting the potential contribution of viral diversification in affecting disease severity.
Abstract
Objective
To date, no information on late-onset infection in newborns to mother with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) contracted in pregnancy are available. This ...study aimed to evaluate postdischarge SARS-CoV-2 status of newborns to mothers with COVID-19 in pregnancy that, at birth, were negative to SARS-CoV-2.
Study Design
This is an observational study of neonates born to mothers with coronavirus disease 2019 (COVID-19).
Results
Seven pregnant women with documented SARS-CoV-2 infection have been evaluated in our institution. One woman had a spontaneous abortion at 8 weeks of gestational age, four women recovered and are still in follow-up, and two women delivered. Two newborns were enrolled in the study. At birth and 3 days of life, newborns were negative to SARS-CoV-2. At 2-week follow-up, one newborn tested positive although asymptomatic.
Conclusion
Our findings highlight the importance of follow-up of newborns to mothers with COVID-19 in pregnancy, since they remain at risk of contracting the infection in the early period of life and long-term consequences are still unknown.
Key Points
Newborns to mothers with coronavirus disease 2019 (COVID-19) in pregnancy can acquire the infection later after birth.
Newborns to mothers with COVID-19 in pregnancy need a long-term follow-up, even if they tested negative at birth.
Specific guidelines for the long-term follow-up of newborns to mothers with COVID-19 in pregnancy are needed.
Many aspects of SARS-CoV-2 infection in children and adolescents remain unclear and optimal treatment is debated. The objective of our study was to investigate epidemiological, clinical and ...therapeutic characteristics of pediatric SARS-CoV-2 infection, focusing on risk factors for complicated and critical disease.
The present multicenter Italian study was promoted by the Italian Society of Pediatric Infectious Diseases, involving both pediatric hospitals and general pediatricians/family doctors. All subjects under 18 years of age with documented SARS-CoV-2 infection and referred to the coordinating center were enrolled from March 2020.
As of 15 September 2020, 759 children were enrolled (median age 7.2 years, IQR 1.4; 12.4). Among the 688 symptomatic children, fever was the most common symptom (81.9%). Barely 47% of children were hospitalized for COVID-19. Age was inversely related to hospital admission (
< 0.01) and linearly to length of stay (
= 0.014). One hundred forty-nine children (19.6%) developed complications. Comorbidities were risk factors for complications (
< 0.001). Viral coinfections, underlying clinical conditions, age 5-9 years and lymphopenia were statistically related to ICU admission (
< 0.05).
Complications of COVID-19 in children are related to comorbidities and increase with age. Viral co-infections are additional risk factors for disease progression and multisystem inflammatory syndrome temporarily related to COVID-19 (MIS-C) for ICU admission.
As the global COVID-19 pandemic progresses, it is paramount to gain knowledge on adaptive immunity to SARS-CoV-2 in children to define immune correlates of protection upon immunization or infection. ...We analyzed anti-SARS-CoV-2 antibodies and their neutralizing activity (PRNT) in 66 COVID-19-infected children at 7 (±2) days after symptom onset. Individuals with specific humoral responses presented faster virus clearance and lower viral load associated with a reduced in vitro infectivity. We demonstrated that the frequencies of SARS-CoV-2-specific CD4+CD40L+ T cells and Spike-specific B cells were associated with the anti-SARS-CoV-2 antibodies and the magnitude of neutralizing activity. The plasma proteome confirmed the association between cellular and humoral SARS-CoV-2 immunity, and PRNT+ patients show higher viral signal transduction molecules (SLAMF1, CD244, CLEC4G). This work sheds lights on cellular and humoral anti-SARS-CoV-2 responses in children, which may drive future vaccination trial endpoints and quarantine measures policies.
Display omitted
•Antibody neutralization is inversely associated with SARS-CoV-2 in nasopharyngeal swabs•Antigen-specific B cells positively associate with anti-SARS-CoV-2 humoral immunity•SARS-CoV-2 neutralizing antibodies are present in patients with higher specific T cells•Antigen-specific B and T cells are features of SARS-CoV-2 immunity in children
Cotugno et al. show that neutralizing antibodies affect SARS-CoV-2 viral load in infected children. Antigen-specific B and T cells are positively associated with virus neutralization. This information provides a basis for defining SARS-CoV-2 adaptive responses in children.
PDF
