Shoubhik Chakraborty

Paediatric Optometrist



Cerebral Visual Impairment (CVI) results from brain damage, affecting visual processing, including the occipital lobe. Some children with CVI retain midbrain-level visual processing through the tecto-pulvinar pathway, enabling better detection of movements and threats.

Visual Pathways and CVI

The visual pathways are complex networks responsible for transmitting visual information from the eyes to the brain. (1) The Retina-geniculo-calcarine pathway, involving the retina, lateral geniculate body, and primary visual cortex in the occipital lobe, is essential for high-level visual processing, allowing us to perceive colours, recognise shapes, and identify objects (Figure 1).

Figure 1: Pathways for visual perception

Picture Courtesy: Danckert J, Striemer C, Rossetti Y. Blindsight. InHandbook of clinical neurology 2021 Jan 1 (Vol. 178, pp. 297-310). Elsevier.

On the other hand, the tecto-pulvinar pathway is considered a lower-level visual processing route, facilitating rapid detection of movements in the environment. Children with CVI may experience damage or dysfunction in the Retina-geniculo-calcarine pathway due to lesions in the occipital lobe, leading to their visual impairments.

Role of the Tecto-pulvinar Pathway

The tecto-pulvinar pathway, (2) although less studied in humans, is well-documented in other vertebrates and plays a vital role in their survival. For instance, snakes rely heavily on this pathway to quickly detect and respond to potential prey, predators, or other objects of interest in their environment. By utilising the tecto-pulvinar pathway, animals can initiate fast visual and motor responses to ensure their survival.

Understanding CVI and its Impact

CVI is a complex condition that can present differently in each affected child, depending on the location and extent of brain damage or dysfunction. Children with CVI often have varying degrees of visual impairment, which can include difficulties in recognising faces, tracking objects, or processing complex visual scenes. Traditional visual assessments may not fully capture the extent of their visual abilities.(3)

Capitalising on Midbrain-Level Visual Processing

In children with CVI, the preserved midbrain-level visual processing through the tecto-pulvinar pathway offers a unique opportunity for intervention. Due to their ability to perceive moving objects better than static ones, clinicians can design specialised training programs to capitalise on this strength.

Training Lower-Level Visual Perceptions

Clinicians can implement clinical interventions that focus on training lower-level visual perceptions, such as motion perception, to enhance the child’s ability to navigate their environment effectively. Activities may include introducing moving objects and encouraging the child to follow or reach for them, promoting interaction with the visual world based on their midbrain-level strengths. (4)

Improved Navigation and Interaction

By utilising the strengths of the tecto-pulvinar pathway, children with CVI can develop improved navigation skills and become more adept at avoiding obstacles or hazards in their path. This can significantly enhance their overall visual experience and independence in daily activities.

Conclusion – Tailored Approach

It is crucial for interventions to be individualised to each child’s specific visual abilities and challenges. Clinicians and therapists should assess the child’s visual strengths and weaknesses, including their proficiency in processing motion, to create personalized training programs that maximise their potential. (5)



  1. Danckert, J., Striemer, C., & Rossetti, Y. (2021). Blindsight. Handbook of clinical neurology178, 297–310.
  2. Bridge, H., Leopold, D. A., & Bourne, J. A. (2016). Adaptive Pulvinar Circuitry Supports Visual Cognition. Trends in cognitive sciences20(2), 146–157.
  3. Zihl, J., & Dutton, G. N. (2016). Cerebral visual impairment in children. Springer Verlag Gmbh.
  4. Kaas, J. H., & Lyon, D. C. (2007). Pulvinar contributions to the dorsal and ventral streams of visual processing in primates. Brain research reviews55(2), 285-296.
  5. Ungerleider, L. G., & Haxby, J. V. (1994). ‘What’and ‘where’in the human brain. Current opinion in neurobiology4(2), 157-165.

Cover picture Courtesy : Image courtesy: