Carnegie Mellon University

Isabel Bleimeister

Isabel BleimeisterMajor: Neuroscience
Minor: Biomedical Engineering
Adviser: Marlene Behrmann

Subcortical Visual Processing

Recent research by Dr. Marlene Behrmann suggests that subcortical regions of the brain may play a role in processing primitive kinds of visual stimuli. By presenting subjects with images of dots varying in number and orientation and using a Wheatstone stereoscope to bisect their vision, Dr. Behrmann uncovered a monocular advantage.

The specific subcortical structures involved in this visual processing are not currently known, but it is likely that the superior colliculus is the portion of the brain involved. Because it does not receive signals from short wavelength cones, purple stimuli are invisible to it.

For my project, I will present participants with purple-tinted images of dots using a Wheatstone stereoscope to determine whether these purple images are unable to uncover the same monocular advantage effect uncovered by greyscale images.

My final thesis will take the form of a journal article that is ready for submission. I will present my research at the Meeting of the Minds Undergraduate Research Symposium and at a departmental poster session and a vision cognition lab group meeting.


My first neuroscience research experience was in eleventh grade, when I reached out to a lab at UCLA that used Transcranial Magnetic Stimulation (TMS) to study movement disorders. My mother had just started a repetitive TMS program aimed at reducing her depression and I sought to improve my understanding of the procedure by learning how to perform it myself.

From this initial research experience, I discovered that I truly enjoy being in an environment that fosters scientific innovation and creativity. Every lecture and discussion I attended acted as a reminder of just how expansive the field of neuroscience actually is, while every presentation I gave served to further instantiate myself in the world of neuroscience research.

A byproduct of this first research experience was that it also gave me an area of commonality with my mother. Suddenly I became her principal source for understanding the treatments she was undergoing. I was by no means an expert, but I had a background in the area and worked to increase that background over time by reading papers and attending lectures that pertained to her conditions. In this way, without meaning to, my mother inspired my passion for neuroscience and research while neuroscience and research helped me to reconnect with my mother.

With such a personal underlying motivation to do research, it is perhaps unsurprising that I remain as intrigued by the field of neuroscience now as I was in high school. Since this first research experience I have studied the lateralization of face-word processing in hemispherectomy patients and have researched the impact of different rehabilitation techniques on traumatic brain injury. I look forward to expanding the breadth of my neuroscience research experience over the coming year by continuing to investigate new areas of the field.