Related Experiment Video
Updated: Aug 24, 2026

Investigating Object Representations in the Macaque Dorsal Visual Stream Using Single-unit Recordings
Published on: August 1, 2018
Functional characteristics of the associative areas of the cortex involved in visual information discrimination
K N Dudkin1, I V Chueva, F N Makarov
1Cognitive Processes Modeling Group and Department of Interneuronal Connections, I. P. Pavlov Institute of Physiology, Russian Academy of Sciences, 6 Makarov Bank, 199034 St. Petersburg, Russia.
Abstract:
Experiments on three groups of rhesus macaques (intact and with bilateral removal of field 7 and the sulcus principalis) were performed to study the functional characteristics of the associative areas of the cortex while the monkeys learned visual discrimination. Significant differences in learning processes associated with removal of structures and the properties of the stimuli were seen in all animals, in the form of different types of learning curves. As compared with intact monkeys, removal of field 7 had no effect on learning processes for images with properties such as spatial frequency, color, and animal images, though there was a significant worsening in the characteristics of learning during visual discrimination of spatial relationships between objects. Learning processes became unstable, the number of peaks and troughs on learning curves increased, and as a result the training periods were significantly lengthened and 85% of the animals were unable to achieve the learning criterion. Removal of the sulcus principalis significantly worsened the characteristics of discrimination of the sizes of geometric objects, the spatial relationships between them, and stimuli of different colors. The stable reaction time and the probability of refusal in most cases also increased for monkeys of both these groups. Cluster analysis based on the quantitative characteristics of learning processes, despite individual differences between the monkeys, demonstrated a tendency for stimuli to be separated into classes corresponding to different types of information. These data show that the result of sensory processing is that several (at least three) functional visual information flows are generated and that different areas of the cortex deal with these different flows.
Related Concept Videos
Motor and Sensory Areas of the Cortex
Motor Areas
The motor areas located in the frontal lobe are central to controlling voluntary movements. This region is further subdivided into the primary motor cortex and the premotor cortex.
Association Areas of the Cortex
Prefrontal Association Area: This area is located in the frontal lobe and is involved in planning, decision-making, and moderating social behavior. It connects with primary motor areas,...
Somatosensory, Motor, and Association Cortex
Vision
Visual System
Once through the pupil, the light passes through the lens, a...
Higher Mental Functions of Brain: Learning and Memory

