Cerebral asymmetries are a fundamental principle of vertebrate brain architecture. These asymmetrical structures are most likely beneficial for various kinds of information processings. Research has shown that the avian brain is highly visually-lateralized. Results display a left hemisphere/right eye advantage in pigeons for object processing. Unfortunately, findings on visuospatial lateralization are ambiguous. In chicks also a left hemisphere dominance for object processing has been shown whereas the right hemisphere is more probable to elicit high performances in visuospatial tasks. Inconsistently, homing pigeons revealed a left-hemispheric superiority for visuospatial orientation. We investigated visuospatial processing in pigeons (Columba livia) with a new experimental paradigm. The subjects were confined in a box with their neck and head protruding through a central circular opening. This opening was surrounded by sixteen concentrically arranged food positions each containing one piece of grain the animals had to peck at. Pigeons were tested alternately under monocular (left/right) and binocular conditions. We measured the time the subjects needed to peck all grains and the extent of visual scanning, operationalized by crossing the circular segments with their head. Although both monocular conditions did not differ with respect to the time needed to finish the task, right-seeing animals needed fewer scans to finish the task. Remarkably, both monocular conditions did not reveal significant differences in number of divers, number of peckfailures and number of direction changes. These findings display a higher efficiency of left hemispheric visuospatial processing. Left-seeing pigeons needed more scans per time than right-seeing birds to consume the grains. In summary, the superiority of the right hemisphere in spatial tasks is not an universal phenomenon of vertebrate brain architecture.
Inhaltsverzeichnis (Table of Contents)
- Abstract
- Introduction
- Methods
- Results
- Discussion
- References
Zielsetzung und Themenschwerpunkte (Objectives and Key Themes)
This research report examines the impact of cerebral asymmetries on visuospatial processing in pigeons. The study seeks to understand the lateralization patterns in the avian brain, particularly in relation to spatial representation and visual processing. The research highlights the importance of lateralization in understanding brain function and its relevance to various neurological disorders.
- Cerebral Asymmetries in the Avian Brain
- Visuospatial Processing in Pigeons
- Lateralization Patterns in Vertebrates
- The Avian Visual System and its Organization
- Neuroanatomical Asymmetries and their Behavioral Consequences
Zusammenfassung der Kapitel (Chapter Summaries)
- Abstract: This chapter introduces the concept of cerebral asymmetries and their potential benefits for information processing. It highlights the existing research on avian brain lateralization, focusing on visual processing and the left hemisphere's dominance in object recognition. However, it acknowledges the ambiguity surrounding visuospatial lateralization in birds, with some studies suggesting a right hemisphere advantage in spatial tasks.
- Introduction: This chapter delves deeper into the significance of cerebral asymmetries in vertebrate brain architecture, particularly in relation to neurological disorders. It discusses the widespread nature of lateralization across vertebrates and emphasizes the unique suitability of the avian brain for research on this topic. The chapter then explores the avian visual system, outlining the two primary visual pathways—tectofugal and thalamofugal—and their roles in processing different types of visual stimuli. It concludes by highlighting the specific neuroanatomical asymmetries in the avian brain, particularly in the tectofugal system, and their potential links to behavioral lateralization.
Schlüsselwörter (Keywords)
This research report focuses on lateralization, spatial representation, and visuospatial processing in the avian brain. It explores the neuroanatomical asymmetries in the tectofugal visual pathway and their impact on behavioral differences. The study utilizes a novel experimental paradigm to investigate the effects of monocular and binocular conditions on spatial tasks, providing insights into the left hemisphere's role in visuospatial processing.
- Quote paper
- Patrick Vollmar (Author), 2003, Asymmetries in visuospatial processing in birds, Munich, GRIN Verlag, https://www.grin.com/document/13291
