Ecological and geographical criteria of species in Quaternary mammals on the example of ground squirrels of the subgenus Colobotis (Sciuridae, Rodentia)

2021 ◽  
pp. 180-195
Author(s):  
Liliia Popova ◽  
Leonid Rekovets
Keyword(s):  
Small Mammals ◽  
Climatic Changes ◽  
Ground Squirrels ◽  
Middle Pleistocene ◽  
Left Bank ◽  
Species Ranges ◽  
Resistant Species ◽  
Left And Right ◽  
The Right

Pleistocene small mammals demonstrate two main types of response to climatic changes: elastic (significant changes of species ranges) and resistant (stable ranges). Extinct ground squirrels of the subgenus Соlobotis belonged to climate-resistant species and formed morphologically distinct subspecies. The dispersal of the Middle Pleistocene Spermophilus (Сolobotis) superciliosus both on the left and right bank of the Dnipro corresponds to the absence of any isolating effect of the river under conditions of tectonic stability. In the Late Pleistocene, under the dominance of tectonic uplift and increasing isolating role of rivers, several subspecies were formed: S. superciliosus palaeodesnensis and S. superciliosus fulvoides on the left bank and another form on the right bank that was morphologically similar to S. major. The major-like form disappeared in the Holocene being replaced by S. s. fulvoides, which came from the Left-Bank Dnipro area.

The role of visual experience for spatial numerical associations

2012 ◽  
Vol 25 (0) ◽  
pp. 222 ◽  
Author(s):  
Michael J. Proulx ◽  
Achille Pasqualotto ◽  
Shuichiro Taya
Keyword(s):  
Visual Experience ◽  
Opposite Effect ◽  
Random Number Generation ◽  
Number Line ◽  
Mental Number Line ◽  
Generation Task ◽  
Congenitally Blind ◽  
Left And Right ◽  
The Right

The topographic representation of space interacts with the mental representation of number. Evidence for such number–space relations have been reported in both synaesthetic and non-synaesthetic participants. Thus far most studies have only examined related effects in sighted participants. For example, the mental number line increases in magnitude from left to right in sighted individuals (Loetscher et al., 2008, Curr. Biol.). What is unclear is whether this association arises from innate mechanisms or requires visual experience early in life to develop in this way. Here we investigated the role of visual experience for the left to right spatial numerical association using a random number generation task in congenitally blind, late blind, and blindfolded sighted participants. Participants orally generated numbers randomly whilst turning their head to the left and right. Sighted participants generated smaller numbers when they turned their head to the left than to the right, consistent with past results. In contrast, congenitally blind participants generated smaller numbers when they turned their head to the right than to the left, exhibiting the opposite effect. The results of the late blind participants showed an intermediate profile between that of the sighted and congenitally blind participants. Visual experience early in life is therefore necessary for the development of the spatial numerical association of the mental number line.

Bihemispheric Language: How the Two Hemispheres Collaborate in the Processing of Language

2004 ◽  
Author(s):  
Norman D. Cook
Keyword(s):  
Language Processing ◽  
Right Hemisphere ◽  
Central Question ◽  
Linguistic Processing ◽  
Figures Of Speech ◽  
Language Functions ◽  
Left And Right ◽  
Level Of Understanding ◽  
The Right

Speech production in most people is strongly lateralized to the left hemisphere (LH), but language understanding is generally a bilateral activity. At every level of linguistic processing that has been investigated experimentally, the right hemisphere (RH) has been found to make characteristic contributions, from the processing of the affective aspects of intonation, through the appreciation of word connotations, the decoding of the meaning of metaphors and figures of speech, to the understanding of the overall coherency of verbal humour, paragraphs and short stories. If both hemispheres are indeed engaged in linguistic decoding and both processes are required to achieve a normal level of understanding, a central question concerns how the separate language functions on the left and right are integrated. This chapter reviews relevant studies on the hemispheric contributions to language processing and the role of interhemispheric communications in cognition.

Cross-modal Processing in the Occipito-temporal Cortex: A TMS Study of the Müller-Lyer Illusion

2011 ◽  
Vol 23 (8) ◽  
pp. 1987-1997 ◽  
Author(s):  
Flavia Mancini ◽  
Nadia Bolognini ◽  
Emanuela Bricolo ◽  
Giuseppe Vallar
Keyword(s):  
Temporal Cortex ◽  
Visual Modality ◽  
Lateral Occipital Complex ◽  
Lyer Illusion ◽  
Superior Parietal Cortex ◽  
Left And Right ◽  
Neural Underpinnings ◽  
The Right ◽  
Underlying Processes

The Müller-Lyer illusion occurs both in vision and in touch, and transfers cross-modally from vision to haptics [Mancini, F., Bricolo, E., & Vallar, G. Multisensory integration in the Müller-Lyer illusion: From vision to haptics. Quarterly Journal of Experimental Psychology, 63, 818–830, 2010]. Recent evidence suggests that the neural underpinnings of the Müller-Lyer illusion in the visual modality involve the bilateral lateral occipital complex (LOC) and right superior parietal cortex (SPC). Conversely, the neural correlates of the haptic and cross-modal illusions have never been investigated previously. Here we used repetitive TMS (rTMS) to address the causal role of the regions activated by the visual illusion in the generation of the visual, haptic, and cross-modal visuo-haptic illusory effects, investigating putative modality-specific versus cross-modal underlying processes. rTMS was administered to the right and the left hemisphere, over occipito-temporal cortex or SPC. rTMS over left and right occipito-temporal cortex impaired both unisensory (visual, haptic) and cross-modal processing of the illusion in a similar fashion. Conversely, rTMS interference over left and right SPC did not affect the illusion in any modality. These results demonstrate the causal involvement of bilateral occipito-temporal cortex in the representation of the visual, haptic, and cross-modal Müller-Lyer illusion, in favor of the hypothesis of shared underlying processes. This indicates that occipito-temporal cortex plays a cross-modal role in perception both of illusory and nonillusory shapes.

An Exploratory TMS Study on Prefrontal Lateralization in Valence Categorization of Facial Expressions

2017 ◽  
Vol 64 (4) ◽  
pp. 282-289 ◽  
Author(s):  
Chiara Ferrari ◽  
Lucile Gamond ◽  
Marcello Gallucci ◽  
Tomaso Vecchi ◽  
Zaira Cattaneo
Keyword(s):  
Facial Expressions ◽  
Emotional Processing ◽  
Right Hemisphere ◽  
Control Site ◽  
Emotional Facial Expressions ◽  
Left Dlpfc ◽  
Dorsolateral Prefrontal ◽  
Left And Right ◽  
The Right

Abstract. Converging neuroimaging and patient data suggest that the dorsolateral prefrontal cortex (DLPFC) is involved in emotional processing. However, it is still not clear whether the DLPFC in the left and right hemisphere is differentially involved in emotion recognition depending on the emotion considered. Here we used transcranial magnetic stimulation (TMS) to shed light on the possible causal role of the left and right DLPFC in encoding valence of positive and negative emotional facial expressions. Participants were required to indicate whether a series of faces displayed a positive or negative expression, while TMS was delivered over the right DLPFC, the left DLPFC, and a control site (vertex). Interfering with activity in both the left and right DLPFC delayed valence categorization (compared to control stimulation) to a similar extent irrespective of emotion type. Overall, we failed to demonstrate any valence-related lateralization in the DLPFC by using TMS. Possible methodological limitations are discussed.

scholarly journals Processing of Words and Faces by Patients with Left and Right Temporal Lobe Epilepsy

1991 ◽  
Vol 4 (2) ◽  
pp. 121-128 ◽  
Author(s):  
Andrew W. Ellis ◽  
Jonathan C. Hillam ◽  
Alistair Cardno ◽  
Janice Kay
Keyword(s):  
Temporal Lobe ◽  
Face Processing ◽  
Reading Tests ◽  
Temporal Lobes ◽  
Control Subjects ◽  
Significant Difference ◽  
Left And Right ◽  
Right Temporal Lobe Epilepsy ◽  
The Right

Tests of word and face processing were given to patients with complex partial epilepsy focussed on the left or right temporal lobe, and to non-epileptic control subjects. The left TLE group showed the greatest impairment on object naming and on reading tests, but the right TLE group also showed a lesser impairment relative to the normal control subjects on both tests. The right TLE group was selectively impaired on distinguishing famous from non-famous faces while the left TLE group was impaired at naming famous faces they had successfully recognized as familiar. There was no significant difference between the three groups on recognition memory for words. The implications of the results for theories of the role of the temporal lobes in word and face processing, and the possible neural mechanisms responsible for the deficits in TLE patients, are discussed.

Bias for the Left Visual Field in Rapid Serial Visual Presentation: Effects of Additional Salient Cues Suggest a Critical Role of Attention

2015 ◽  
Vol 27 (2) ◽  
pp. 266-279 ◽  
Author(s):  
Kamila Śmigasiewicz ◽  
Dariusz Asanowicz ◽  
Nicole Westphal ◽  
Rolf Verleger
Keyword(s):  
Visual Field ◽  
Left Visual Field ◽  
Right Hemisphere ◽  
Critical Role ◽  
Visual Presentation ◽  
The Other ◽  
Early Posterior Negativity ◽  
Left And Right ◽  
The Right

Everyday experience suggests that people are equally aware of stimuli in both hemifields. However, when two streams of stimuli are rapidly presented left and right, the second target (T2) is better identified in the left hemifield than in the right hemifield. This left visual field (LVF) advantage may result from differences between hemifields in attracting attention. Therefore, we introduced a visual cue shortly before T2 onset to draw attention to one stream. Thus, to identify T2, attention was correctly positioned with valid cues but had to be redirected to the other stream with invalid ones. If the LVF advantage is caused by differences between hemifields in attracting attention, invalid cues should increase, and valid cues should reduce the LVF advantage as compared with neutral cues. This prediction was confirmed. ERP analysis revealed that cues evoked an early posterior negativity, confirming that attention was attracted by the cue. This negativity was earlier with cues in the LVF, which suggests that responses to salient events are faster in the right hemisphere than in the left hemisphere. Valid cues speeded up, and invalid cues delayed T2-evoked N2pc; in addition, valid cues enlarged T2-evoked P3. After N2pc, right-side T2 evoked more sustained contralateral negativity than left T2, least long-lasting after valid cues. Difficulties in identifying invalidly cued right T2 were reflected in prematurely ending P3 waveforms. Overall, these data provide evidence that the LVF advantage is because of different abilities of the hemispheres in shifting attention to relevant events in their contralateral hemifield.

scholarly journals Distributing and delivering vessels of the human heart.

1988 ◽  
Vol 91 (5) ◽  
pp. 725-735 ◽  
Author(s):  
M Zamir
Keyword(s):  
Coronary Arteries ◽  
Human Heart ◽  
Functional Difference ◽  
Functional Classification ◽  
Functional Importance ◽  
Left And Right ◽  
Obtuse Marginal ◽  
The Right

The branching characteristics of the right coronary artery, acute marginal, posterior descending, left anterior descending, circumflex, and obtuse marginal arteries are compared with those of diagonal branches, left and right ventricular branches, septal, and higher-order branches, to test a newly proposed functional classification of the coronary arteries in which the first group rank as distributing vessels and the second as delivering vessels. According to this classification, the function of the first type is merely to convey blood to the borders of myocardial zones, while the function of the second is to implement the actual delivery of blood into these zones. This functional difference is important in the hemodynamic analysis of coronary heart disease, as it provides an assessment of the role of a vessel within the coronary network and hence an assessment of the functional importance of that vessel in a particular heart. Measurements from casts of human coronary arteries are used to examine the relevant characteristics of these vessels and hence to test the basis of this classification.

Zoonoses as factor of evolution, population dynamics, and speciation

2021 ◽  
pp. 153-172
Author(s):  
Igor Evstafiev ◽  
Igor Zagorodniuk
Keyword(s):  
Population Dynamics ◽  
Small Mammals ◽  
Population Diversity ◽  
Crimean Peninsula ◽  
Species Ranges ◽  
Animal Populations ◽  
Tick Borne Encephalitis ◽  
Evolutionary Changes ◽  
Population Numbers

The role of zoonoses in changes of animal populations and communities is considered. The analysis was carried out using examples of population dynamics of small mammals distributed in the Crimean Peninsula, under the influence of the main zoonoses common for this territory, in particular tularaemia, leptospirosis, Marseille fever, viral tick-borne encephalitis, Ixodes tick-borne borreliosis, Crimea-Congo fever, KU fever, HFRS, and many others. Such data were analysed according to databases on the state of small-mammal populations and zoonoses common in these populations, obtained by original studies over the past 40 years. The role of zoonoses as factors of evolutionary changes in populations of small mammals is considered, in particular as a factor of mortality leading to significant reductions in population numbers and fragmentation of species ranges, as well as factors determining co-evolution of pathogens, vectors (arthropods), and small-mammals as hosts. Both groups of factors lead to the formation of population diversity due to changes in character variability and the formation of new characters associated with adaptations to zoonoses.

Troubles de l'orientation spatiale dans une épreuve de recherche d'itinéraire lors des lésions corticales unilaterales

Perception ◽  
1972 ◽  
Vol 1 (3) ◽  
pp. 325-330 ◽  
Author(s):  
H Hécaen ◽  
C Tzortzis ◽  
M C Masure
Keyword(s):  
Right Hemisphere ◽  
Parietal Lobe ◽  
Cortical Lesions ◽  
Route Finding ◽  
Left And Right ◽  
The Right ◽  
Better Than ◽  
Parietal Lesion

Previous studies on brain-damaged patients have shown impairments in orientation. When the results have been based on a route-finding test the impairment was found in both left and right parietal lesion groups, while when maze tests have been used, the impairment correlated clearly only with lesions of the right hemisphere. In the present study the route-finding test was given to 77 right-handed patients with unilateral cortical lesions (33 right-sided, and 44 left-sided), and to 24 controls. In order to evaluate the possible influence of kinesthetic afferents, the test was carried out under two different conditions: active (walking) and passive (in a pushchair). The results show the performances of subjects with lesions on the left side are significantly poorer than those of the controls, but better than those of subjects with lesions on the right side. For both groups the impairment associated with the lesion is the same under active and passive conditions, which does not support the hypothesis of the possible role of the kinesthetic afferents. Posterior lesions produce significantly more failures in both groups. The importance of the parietal lobe, however, was clearly seen only in subjects with lesions on the right side.

Role of Anterior and Posterior Attention Networks in Hemispheric Asymmetries during Lexical Decisions

1991 ◽  
Vol 3 (4) ◽  
pp. 313-321 ◽  
Author(s):  
Atsuko Nakagawa
Keyword(s):  
Left Hemisphere ◽  
Right Hemisphere ◽  
Visual Fields ◽  
Reaction Times ◽  
Attention Networks ◽  
Priming Task ◽  
Left And Right ◽  
The Right ◽  
Prime Target

The role of the left and right hemisphere was examined during semantic priming by antonyms, remote associates, and unrelated words. Targets presented directly to the left hemisphere showed an early facilitation and a late developing inhibition, while targets presented directly to the right hemisphere showed a late developing facilitation of strong and weak associations and little evidence of inhibition. When a visual cue was given prior to each target word, reaction times were facilitated equally in both visual fields and for all prime target relationships. When the priming task was combined with shadowing, reaction times generally increased and all evidence of inhibition in left hemisphere processing disappeared. This supported the idea that the inhibition found in the left hemisphere was due to its interaction with the anterior attention network.

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