Visual Working Memory

Visual working memory (VWM) is a broader term used to describe two very different functions – visual short-term memory and visual working memory. Visual short-term memory describes the storage aspect of memory; while visual working memory is used to describe both the storage and the manipulation of information held in memory. Poor visual working memory performance has been linked to several common childhood disorders; including ADHD, autism, developmental coordination disorder, and others.

Visual working memory (VWM) is a core cognitive function in which we perceive the identity of objects and perceive where objects are located in space at any given point in time to help focus attention. Research has shown that these two types of information (identification and perception) are performed by two different neural processing paths, one ventral, the other dorsal.

The ventral path is used for perceiving the identity of objects, and the dorsal path for perceiving where objects are located in space. Both processing paths begin in the primary visual cortex. However, the ventral path travels the inferior temporal cortex; while the dorsal path travels through the posterior parietal cortex. It is also believed that this cognitive division continues into the frontal lobes and influences how the frontal lobes process working memory information.

Attention and working memory impose capacity limitations in cognitive processing. Visual working memory allows us to hold a visual picture in our mind for a few seconds after it disappears from our sight. During this time span of a few seconds, a small subset is transferred into visual working memory. The capacity of visual working memory for adults is limited to approximately four visual items; while three year olds have a capacity of 1.3 visual items, and 4 year olds reach a capacity of 1.8 items. Visual working memory increases with age. Capacity of visual items varies little with differences in colors, size, familiarity, etc.

As humans, we can recognize an object in a single glimpse, yet are unable retain more than four objects at a time as adults in visual working memory (VWM). It has been shown that an individual does not retain more familiar information as compared to unfamiliar information. With regard to the role of learning, visual working memory relies on the prioritization of a subset of visual displays. This type of prioritization occurs only if a subset is designated as more important than other subsets. Consistent association allows the subset to be prioritized, whereas non-associative learning does not.

While visual working memory has limited capacity, long-term memory has virtually unlimited capacity. It is important to note, that information that is to be remembered and transferred to long-term memory must first be stored in working memory. This is why working memory plays a central role in learning. Visual working memory has limited storage and processing capacity, and information is normally forgotten over time, unless the information is repeated.

As an example, students rely on working memory when they are trying to remember information for short periods of time, or when they work on cognitively demanding tasks. Working memory represents an expansion and modification of the information that is stored in long-term memory. Reduced working memory capacity can lead to increased incidences of distraction, problems beginning and sustaining tasks over time, difficulties organizing work, as well as difficulty receiving and remembering instructions. Students with reduced visual working memory can experience learning difficulties, particularly in the areas of mathematics and reading instruction.

Poor visual working memory can contribute to the struggles experienced by individuals with autism. Study results suggest that individuals with autism have a much worse visual working memory as compared to the general population. Visual working memory functions much like a mental blackboard. Individuals with poor visual working memory have increased difficulty understanding math concepts or solving math problems in their head – even simple addition and subtraction problems.

Similar studies suggest that visual working memory may play an important role in developing social skills in children with autism. We use visual working memory to read body language and pickup other social cues in order to respond appropriately. Individuals who have challenges processing nonverbal communication are more likely to experience awkwardness in social settings.

Visual working memory (VWM) affects everyone; impacting how we learn, our social interactions, and job performance. Future research into the area of visual working memory is necessary to acquire a better understanding of the cognitive function within the brain.