scholarly journals Lateral Asymmetry of Brain and Behaviour in the Zebra Finch, Taeniopygia guttata

Symmetry ◽  
2018 ◽  
Vol 10 (12) ◽  
pp. 679 ◽  
Author(s):  
Lesley Rogers ◽  
Adam Koboroff ◽  
Gisela Kaplan
Keyword(s):  
Visual Field ◽  
Zebra Finch ◽  
Visual Processing ◽  
Right Hemisphere ◽  
General Pattern ◽  
Zebra Finches ◽  
Hemispheric Differences ◽  
Lateral Asymmetry ◽  
Monitor Lizard ◽  
Eye Preference

Lateralisation of eye use indicates differential specialisation of the brain hemispheres. We tested eye use by zebra finches to view a model predator, a monitor lizard, and compared this to eye use to view a non-threatening visual stimulus, a jar. We used a modified method of scoring eye preference of zebra finches, since they often alternate fixation of a stimulus with the lateral, monocular visual field of one eye and then the other, known as biocular alternating fixation. We found a significant and consistent preference to view the lizard using the left lateral visual field, and no significant eye preference to view the jar. This finding is consistent with specialisation of the left eye system, and right hemisphere, to attend and respond to predators, as found in two other avian species and also in non-avian vertebrates. Our results were considered together with hemispheric differences in the zebra finch for processing, producing, and learning song, and with evidence of right-eye preference in visual searching and courtship behaviour. We conclude that the zebra finch brain has the same general pattern of asymmetry for visual processing as found in other vertebrates and suggest that, contrary to earlier indications from research on lateralisation of song, this may also be the case for auditory processing.

Right Hemisphere Memory Bias Does Not Extend to Involuntary Memories for Negative Scenes

Perception ◽  
2021 ◽  
Vol 50 (1) ◽  
pp. 27-38
Author(s):  
Ella K. Moeck ◽  
Nicole A. Thomas ◽  
Melanie K. T. Takarangi
Keyword(s):  
Visual Field ◽  
Left Hemisphere ◽  
Right Hemisphere ◽  
Visual Fields ◽  
Memory Bias ◽  
Right Visual Field ◽  
Hemispheric Differences ◽  
Involuntary Memory ◽  
Involuntary Memories ◽  
The Right

Attention is unequally distributed across the visual field. Due to greater right than left hemisphere activation for visuospatial attention, people attend slightly more to the left than the right side. As a result, people voluntarily remember visual stimuli better when it first appears in the left than the right visual field. But does this effect—termed a right hemisphere memory bias—also enhance involuntary memory? We manipulated the presentation location of 100 highly negative images (chosen to increase the likelihood that participants would experience any involuntary memories) in three conditions: predominantly leftward (right hemisphere bias), predominantly rightward (left hemisphere bias), or equally in both visual fields (bilateral). We measured subsequent involuntary memories immediately and for 3 days after encoding. Contrary to predictions, biased hemispheric processing did not affect short- or long-term involuntary memory frequency or duration. Future research should measure hemispheric differences at retrieval, rather than just encoding.

scholarly journals Exploration of the Hemispheric Differences in Number Processing of the Brain

2012 ◽  
Vol 1 (2) ◽  
pp. 55-61
Author(s):  
Aaron Wyland Walters
Keyword(s):  
Reaction Time ◽  
Visual Field ◽  
Right Hemisphere ◽  
Visual Fields ◽  
Reaction Time Data ◽  
Right Visual Field ◽  
Hemispheric Differences ◽  
Time Data ◽  
Central Target ◽  
The Right

Abstract The current study explored how reaction time and accuracy differed in the left and right visual fields by altering various dot clusters in both number and organization. Researchers have hypothesized that the left hemisphere uses counting to judge small, disorganized clusters of objects accurately and that the right hemisphere uses estimation to judge clusters organized in geometric shape accurately. The current study tested both visual fields of participant’s with organized and unorganized clusters of dots. Dots were clustered between 3 and 12. The clusters were presented on separate sides of a computer screen to analyze visual field differences in counting and estimation. A central target was presented on the screen to maintain central focus for the visual fields. Data from 40 participants (30 men, 10 women) from a small liberal arts college indicated that when clusters reached between 7 and 8 dots, organization in the right visual field created inaccuracy in judgment. Reaction time data indicated that as number level increased, reaction time slowed. Reaction time data also showed that organization slowed reaction times in both visual fields. These data indicated that different numerical judgment abilities do exist within the hemispheres.

Attention and Hemispheric Differences in Reaction Time during Simultaneous Audio-Visual Tasks

1973 ◽  
Vol 25 (3) ◽  
pp. 404-412 ◽  
Author(s):  
Gina Geffen ◽  
J. L. Bradshaw ◽  
N. C. Nettleton
Keyword(s):  
Reaction Time ◽  
Visual Field ◽  
Right Hemisphere ◽  
Visual Fields ◽  
Normal Subjects ◽  
Auditory Task ◽  
Right Visual Field ◽  
Hemispheric Differences ◽  
Language Functions ◽  
The Right

The effect of different types of competing auditory tasks on laterality differences in visual perception was investigated. Right-handed subjects were presented with digits which occurred randomly in the left or right visual fields. They responded vocally to previously specified digits in a go, no-go reaction time situation. In the absence of any competing auditory task, digits presented in the right visual field were processed more quickly. This visual field difference in reaction time was in the same direction while subjects performed a secondary musical task. However, when a secondary verbal task had to be performed, digits in the left visual field received faster responses. The results support the view that the right hemisphere is capable of some language functions, and that hemispheric differences in performance have at their basis a quantitative asymmetry, which can be reversed even in normal subjects by overloading their limited capacity.

Recognition of CVC Syllables from LVF, RVF, and Central Locations: Hemispheric Differences and Interhemispheric Interaction

1995 ◽  
Vol 7 (2) ◽  
pp. 258-266 ◽  
Author(s):  
Joseph B. Hellige ◽  
Elizabeth L. Cowin ◽  
Tami L. Eng
Keyword(s):  
Visual Field ◽  
Left Hemisphere ◽  
Right Hemisphere ◽  
The Other ◽  
Right Visual Field ◽  
Interhemispheric Interaction ◽  
Hemispheric Differences ◽  
Qualitative Pattern ◽  
Nonsense Syllables

In each of two experiments, subjects were required to identify consonant-vowel-consonant nonsense syllables projected to the left visual fiel/right hemisphere (LVF/RH), right visual field/left hemisphere (RVF/LH), or to the CENTER of the visual field. There were fewer errors on RVF/LH than on LVF/RH trials and the pattern of errors was qualitatively different on RVF/LH and LVF/RH trials. The pattern of errors was consistent with the hypothesis that attention is distributed across the three letters in a relatively slow serial fashion on LVF/RH trials whereas attention is distributed more rapidly and evenly across the three letters on RVF/LH trials. Despite the large RVF/LH advantage, the qualitative pattern of errors on CENTER trials (when viewing conditions do not favor one hemisphere or the other) was very similar to the pattern obtained on LW/RH trials. Implications of this counterintuitive finding are considered for the nature of interhemispheric interaction.

scholarly journals Multiple adjoining word and face selective regions in ventral temporal cortex exhibit distinct dynamics

2020 ◽  
Author(s):  
Matthew J. Boring ◽  
Edward H. Silson ◽  
Michael J. Ward ◽  
R. Mark Richardson ◽  
Julie A. Fiez ◽  
...  
Keyword(s):  
Visual Field ◽  
Left Hemisphere ◽  
Visual Processing ◽  
Word Processing ◽  
Right Hemisphere ◽  
Temporal Dynamics ◽  
Temporal Cortex ◽  
7 Tesla ◽  
Important Principle ◽  
Ventral Temporal Cortex

AbstractThe map of category-selectivity in human ventral temporal cortex (VTC) provides organizational constraints to models of object recognition. One important principle is lateral-medial response biases to stimuli that are typically viewed in the center or periphery of the visual field. However, little is known about the relative temporal dynamics and location of regions that respond preferentially to stimulus classes that are centrally viewed, like the face and word processing networks. Here, word- and face-selective regions within VTC were mapped using intracranial recordings from 36 patients. Partially overlapping, but also anatomically dissociable patches of face and word selectivity were found in ventral temporal cortex. In addition to canonical word-selective regions along the left posterior occipitotemporal sulcus, selectivity was also located medial and anterior to face-selective regions on the fusiform gyrus at the group level and within individual subjects. These regions were replicated using 7-Tesla fMRI in healthy subjects. Left hemisphere word-selective regions preceded right hemisphere responses by 125 ms, potentially reflecting the left hemisphere bias for language; with no hemispheric difference in face-selective response latency. Word-selective regions along the posterior fusiform responded first, then spread medially and laterally, then anteriorally. Face-selective responses were first seen in posterior fusiform regions bilaterally, then proceeded anteriorally from there. For both words and faces, the relative delay between regions was longer than would be predicted by purely feedforward models of visual processing. The distinct time-courses of responses across these regions, and between hemispheres, suggest a complex and dynamic functional circuit supports face and word perception.Significance StatementRepresentations of visual objects in the human brain have been shown to be organized by several principles, including whether those objects tend to be viewed centrally or in the periphery of the visual field. However, it remains unclear how regions that process objects that are viewed centrally, like words and faces, are organized relative to one another. Here, direct neural recordings and 7T fMRI demonstrate that several intermingled regions in ventral temporal cortex participate in word and face processing. These regions display differences in their temporal dynamics and response characteristics, both within and between brain hemispheres, suggesting they play different roles in perception. These results illuminate extended, bilateral, and dynamic brain pathways that support face perception and reading.

Visual field deficits following laser ablation of the hippocampus

Neurology ◽  
2020 ◽  
Vol 94 (12) ◽  
pp. e1303-e1313 ◽  
Author(s):  
Cristian Donos ◽  
Patrick Rollo ◽  
Kathryn Tombridge ◽  
Jessica A. Johnson ◽  
Nitin Tandon
Keyword(s):  
Visual Field ◽  
Right Hemisphere ◽  
Mesial Temporal Lobe Epilepsy ◽  
Temporal Lobectomy ◽  
Hemispheric Differences ◽  
Patient Counseling ◽  
Individual Subject ◽  
Anterior Temporal Lobectomy ◽  
Visual Field Deficits ◽  
Reported Data

ObjectiveTo qualify the incidence of and risk factors for visual field deficits (VFD) following laser interstitial thermal ablation (LITT) for mesial temporal lobe epilepsy (MTLE) and to relate this to anterior temporal lobectomy (ATL).MethodsFifty-seven patients underwent LITT of the amygdalo-hippocampal complex (AH) for MTLE. Masks of ablation volumes, laser probe trajectories, and visual radiations (VRs) from individual subject space were transformed into standardized space using nonlinear registration. Voxel-wise statistics were performed to model relationships between VFDs vs ablation volumes, laser trajectories, VRs, and AH asymmetry. A review of VFDs following ATLs was performed.ResultsThe incidence of VFD after LITT is much lower than after ATLs. A total of 37.5% of patients developed a VFD, with the probability of this being much higher after left (50%) vs right hemisphere LITT (10%) (Fisher test, p = 0.05). This laterality effect on VFDs is mirrored but underappreciated in ATL series. The most consistent LITT-VFD occurred in the superior vertical octant. Ablation of Meyer loop as well as the summed probability of VRs within laser trajectories correlated with VFDs (p < 0.05). Left and right hippocampi have significantly distinct orientations in axial and coronal planes, which may be one reason for the variation in VFD probability.ConclusionsLITT results in lower rates of and smaller VFDs—typically an octantanopsia. VRs are at greater risk during surgery for left than right MTLE. Anatomical asymmetries in hippocampal anatomy may explain the hemispheric differences in deficits, and should factor into trajectory planning and also into preoperative patient counseling. Overall the incidence and extent of visual deficits following LITT for MTLE is lower than the reported data following anterior temporal lobectomy. VF tractography incorporated into LITT planning may reduce the occurrence of VFDs.

scholarly journals The role of prefrontal cortex in working memory: examining the contents of consciousness

1998 ◽  
Vol 353 (1377) ◽  
pp. 1819-1828 ◽  
Author(s):  
◽  
S. M. Courtney ◽  
L. Petit ◽  
J. V. Haxby ◽  
L. G. Ungerleider
Keyword(s):  
Working Memory ◽  
Prefrontal Cortex ◽  
Visual Processing ◽  
Right Hemisphere ◽  
Functional Organization ◽  
Spatial Working Memory ◽  
Domain Specificity ◽  
Long Term Memory ◽  
Present Evidence ◽  
The Right

Working memory enables us to hold in our ‘mind's eye’ the contents of our conscious awareness, even in the absence of sensory input, by maintaining an active representation of information for a brief period of time. In this review we consider the functional organization of the prefrontal cortex and its role in this cognitive process. First, we present evidence from brain–imaging studies that prefrontal cortex shows sustained activity during the delay period of visual working memory tasks, indicating that this cortex maintains on–line representations of stimuli after they are removed from view. We then present evidence for domain specificity within frontal cortex based on the type of information, with object working memory mediated by more ventral frontal regions and spatial working memory mediated by more dorsal frontal regions. We also propose that a second dimension for domain specificity within prefrontal cortex might exist for object working memory on the basis of the type of representation, with analytic representations maintained preferentially in the left hemisphere and image–based representations maintained preferentially in the right hemisphere. Furthermore, we discuss the possibility that there are prefrontal areas brought into play during the monitoring and manipulation of information in working memory in addition to those engaged during the maintenance of this information. Finally, we consider the relationship of prefrontal areas important for working memory, both to posterior visual processing areas and to prefrontal areas associated with long–term memory.

scholarly journals Multivariate EEG analyses support high-resolution tracking of feature-based attentional selection

2016 ◽  
Author(s):  
Johannes Jacobus Fahrenfort ◽  
Anna Grubert ◽  
Christian N. L. Olivers ◽  
Martin Eimer
Keyword(s):  
Visual Field ◽  
Multivariate Analyses ◽  
Target Selection ◽  
Target Position ◽  
Attentional Selection ◽  
Forward Model ◽  
Hemispheric Differences ◽  
Neural Basis ◽  
Eeg Data ◽  
Feature Based

AbstractThe primary electrophysiological marker of feature-based selection is the N2pc, a lateralized posterior negativity emerging around 180-200 ms. As it relies on hemispheric differences, its ability to discriminate the locus of focal attention is severely limited. Here we demonstrate that multivariate analyses of raw EEG data provide a much more fine-grained spatial profile of feature-based target selection. When training a pattern classifier to determine target position from EEG, we were able to decode target positions on the vertical midline, which cannot be achieved using standard N2pc methodology. Next, we used a forward encoding model to construct a channel tuning function that describes the continuous relationship between target position and multivariate EEG in an eight-position display. This model can spatially discriminate individual target positions in these displays and is fully invertible, enabling us to construct hypothetical topographic activation maps for target positions that were never used. When tested against the real pattern of neural activity obtained from a different group of subjects, the constructed maps from the forward model turned out statistically indistinguishable, thus providing independent validation of our model. Our findings demonstrate the power of multivariate EEG analysis to track feature-based target selection with high spatial and temporal precision.Significance StatementFeature-based attentional selection enables observers to find objects in their visual field. The spatiotemporal profile of this process is difficult to assess with standard electrophysiological methods, which rely on activity differences between cerebral hemispheres. We demonstrate that multivariate analyses of EEG data can track target selection across the visual field with high temporal and spatial resolution. Using a forward model, we were able to capture the continuous relationship between target position and EEG measurements, allowing us to reconstruct the distribution of cortical activity for target locations that were never shown during the experiment. Our findings demonstrate the existence of a temporally and spatially precise EEG signal that can be used to study the neural basis of feature-based attentional selection.

scholarly journals A P300 brain-computer interface with a reduced visual field

2020 ◽  
Author(s):  
Luiza Kirasirova ◽  
Vladimir Bulanov ◽  
Alexei Ossadtchi ◽  
Alexander Kolsanov ◽  
Vasily Pyatin ◽  
...  
Keyword(s):  
Visual Field ◽  
Visual Processing ◽  
Peripheral Vision ◽  
Brain Computer Interface ◽  
Basic Research ◽  
Computer Interface ◽  
Eye Tracker ◽  
Central Visual Field ◽  
P300 Speller ◽  
User Fatigue

AbstractA P300 brain-computer interface (BCI) is a paradigm, where text characters are decoded from visual evoked potentials (VEPs). In a popular implementation, called P300 speller, a subject looks at a display where characters are flashing and selects one character by attending to it. The selection is recognized by the strongest VEP. The speller performs well when cortical responses to target and non-target stimuli are sufficiently different. Although many strategies have been proposed for improving the spelling, a relatively simple one received insufficient attention in the literature: reduction of the visual field to diminish the contribution from non-target stimuli. Previously, this idea was implemented in a single-stimulus switch that issued an urgent command. To tackle this approach further, we ran a pilot experiment where ten subjects first operated a traditional P300 speller and then wore a binocular aperture that confined their sight to the central visual field. Visual field restriction resulted in a reduction of non-target responses in all subjects. Moreover, in four subjects, target-related VEPs became more distinct. We suggest that this approach could speed up BCI operations and reduce user fatigue. Additionally, instead of wearing an aperture, non-targets could be removed algorithmically or with a hybrid interface that utilizes an eye tracker. We further discuss how a P300 speller could be improved by taking advantage of the different physiological properties of the central and peripheral vision. Finally, we suggest that the proposed experimental approach could be used in basic research on the mechanisms of visual processing.

scholarly journals A sex chromosome inversion is associated with copy number variation of mitochondrial DNA in zebra finch sperm

2019 ◽  
Author(s):  
Ulrich Knief ◽  
Wolfgang Forstmeier ◽  
Bart Kempenaers ◽  
Jochen B. W. Wolf
Keyword(s):  
Mitochondrial Dna ◽  
Zebra Finch ◽  
Copy Number ◽  
Sex Chromosome ◽  
Data Availability ◽  
Species Variation ◽  
Zebra Finches ◽  
Chromosome Inversion ◽  
Atp Production ◽  
Sperm Midpiece

AbstractPropulsion of sperm cells via movement of the flagellum is of vital importance for successful fertilization. Presumably, the energy for this movement comes from the mitochondria in the sperm midpiece. Larger midpieces may contain more mitochondria, which should enhance the energetic capacity and hence promote mobility. Due to an inversion polymorphism on their sex chromosome TguZ, zebra finches (Taeniopygia guttata castanotis) exhibit large within-species variation in sperm midpiece length, and those sperm with the longest midpieces swim the fastest. Here, we test through quantitative real-time PCR in zebra finch ejaculates whether the inversion genotype has an effect on the copy number of mitochondrial DNA. Taking the inversion genotype as a proxy for midpiece length, we find that zebra finches with longer midpieces indeed have more copies of the mitochondrial DNA in their ejaculates than those with shorter midpieces, with potential downstream effects on the rate of ATP production and sperm swimming speed. This study sheds light on the proximate cause of a fitness-relevant genetic polymorphism, suggesting the involvement of central components of gamete energy metabolism.Data availabilitySupplementary data file

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