Final answer:
Difficulty with spatial-perceptual tasks suggests a lesion in the right hemisphere of the brain, which is associated with spatial recognition and non-verbal tasks.
Step-by-step explanation:
Difficulty with spatial-perceptual tasks and grasping the whole idea of a task or activity is typically associated with a lesion in the right hemisphere of the brain. This hemisphere is known for its role in non-verbal tasks, spatial perception, and recognition of objects, faces, and patterns. For instance, research with split-brain patients, who had their corpus callosum cut to treat severe epilepsy, shows difficulty in verbalizing objects presented to their left visual field; the visual information goes to the right hemisphere and cannot easily cross to the left hemisphere's language centers. The right hemisphere is also important for processing sensory information that results in spatial recognition and awareness.
Conversely, the left hemisphere is often linked with language, mathematical calculation, and logical reasoning. If one side is not perceived during a test such as double simultaneous stimulation, this may indicate damage to the contralateral posterior parietal lobe in the right hemisphere. For complex spatial tasks that require the integration of different sensory inputs to understand the entire concept or layout of a task, damage to the right hemisphere is often the cause of such difficulties.