Lawrence W. Barsalou

Lawrence W. Barsalou, born on November 3, 1951 in San Diego (California/USA), is a psychologist and a cognitive scientist. He received a bachelors degree in Psychology from the University of California, San Diego in 1977, and a Ph.D. in Psychology from Stanford University in 1981. His doctoral advisor was Gordon Bower. Since then, Barsalou has held faculty positions at Emory University, the Georgia Institute of Technology, and the University of Chicago.

His work addresses the nature of human knowledge, and its roles in perception, memory, language, and thought. The current theme of his research is that the human conceptual system is grounded in the brain’s modality-specific systems. Specific topics of interest include whether (and if so, how) modality-specific systems implement symbolic operations and abstract concepts, which is one of the main tasks of current cognitive psychology. Other lines of research address the situated character of knowledge, the dynamic online construction of conceptual representations, the development of ad hoc categories to support goal achievement, the structure of knowledge, and category learning.

Barsalou has endeavored to explain representations in terms of the different modalities of experience, a process termed “grounding” cognition. One of the key processes in Barsalou’s view is multimodal simulation, which, he proposes, constitutes grounded representations.

Simulation

Simulation, in the context of grounded cognition, is the reenactment of neural states from the modalities for perception, action, and introspection. During an experience of an object, elements of these states are “captured” and associated together; later, when knowledge of the object is required, these multimodal states are reactivated to simulate the brain’s original activation as-if the object was actually being experienced.^[1][2][3] For example, when you imagine a cat you re-experience some of the previous sensory inputs (orange, soft, stinky, etc.), motor possibilities (patting, kicking, etc.), and introspective states (annoyance, fear, etc.) that you have experienced when interacting with cats in real time. The thought of a cat is therefore the simultaneous activation of some of the relevant firing patterns in these modalities that would also be activated if actually seeing a cat. Besides being used in active imagination, simulation has been implicated in a variety other unconscious processes.^{[4][5][6][7][8]}

Evidence of the important role simulation plays in cognitive processing can be found in research in neuroscience and behavioral studies. For example, in TMS studies it has been shown that during stimulation of parts of the motor cortex that are active during leg motions comprehension of sentences describing activities dealing with legs is improved. Similar results have been shown with arms.^[9] These results have been taken to indicate a link between motor areas and cognitive processing.

The Modal Systems

A concerted activation of the modalities in simulation constitutes the representations that make all of cognition possible. Barsalou has proposed three systems of modalities that constitute simulations: perceptual, motor, and introspective.^[1] Each of these categories is further subdivided into individual modalities that are responsible for different elements of experience. As mentioned above, each of the modalities operates in close coordination with the others.

The perceptual modalities are the easiest to identify and conceptualize. Each of the senses is a modality: touch, taste, smell, audition, vision, etc. During multimodal simulations neural circuits in sensory modalities that have been “captured” during encounters with whatever is being simulated are reactivated. These re-experienced sensory states constitute the representation.

The motor modalities that Barsalou specifically identifies are movement, proprioception, space, and distance.^[10] When one represents an object the motor circuits for acting upon that object fire in its simulation.

The introspective modalities that Barsalou mentions are mental states, affects, and motivation. Affects are interoceptions presumably of the phenomenal experience of emotions and urges. Mental states include attention, executive processing, memory, reasoning, and language.^[11]

According to Barsalou, simulation composed of these three modalities creates representations and all of the contents of cognition. Associations between them are learned possibly through a neural architecture similar to the convergence/divergence zone proposed by Damasio and colleagues.^[12][13][14] Furthermore, multimodal simulations can be applied to abstract concepts that seem to be impossible to ground in experience. The concept of time, for example, can be represented in the motor modalities of space and distance (time moves forward and the past becomes more distant ), and the concept of beauty can be represented by the introspective state of desire and a sampling of sensory impressions typically considered aesthetically pleasant.^[15][16]

Multimodal representations can be used symbolically in mental computations or they can be implemented in embodied theories to explain “representation-hungry” cognition such as imagination.^[4]

Selected bibliography

• Barsalou, Lawrence. Cognitive psychology: An overview for cognitive scientists. (1992) Lawrence Erlbaum Associates. ISBN 978-0898599664.

References

External links

• The homepage of Lawrence Barsalou at Emory University