Operations of cognition: understanding the Stroop effect1 June 2020
A two-way street: aligned progress in theories of cognition and neuroimaging1 June 2020
Human perception has a bandwidth problem
Human perception and attention are intrinsically linked cognitive processes. Perception is the process of stimuli recognition and interpretation through the five senses, while attention is the selection process of these perceptual systems (Broadbent, 1958). Mediator classifiers include psychological, cognitive and interaction effects as well as neurological impairments.
Allport (1987) first identified the role selection plays in perception (cited in Pratt et al., 2015). Rizzolatti and colleagues’ (1987) developed this thinking into the premotor theory of attention, which coupled attention and eye movements. The study showed shifts of attention corresponded with anatomical constraints of eye movements. Small benefits and high attentional costs were associated with correct and incorrect attention orientations, respectively (Rizzolatti et al., 1987).
This reciprocal relationship was later extended to eye position in visuospatial attention Craighero (2004) and shared cortical networks were implicated in a study of sixth nerve palsy patients which demonstrated effects of neurological impairments on visuospatial attention (Craighero, 2001). Separately, neuroscience studies have implicated the central amygdala (CeA) in mediating selective and sustained attention (Smith et al., 2015).
Mogg and Bradly (2002) demonstrated an interaction effect between selective attention and cognitive biases in visual perception. In the study, highly anxious individuals responded faster to brief visual images of masked faces (i.e. a specific phobia threat cue), compared with neutral faces.
Many processes that influence perception and attention are nonconscious. These include attention control, intentional actions, choices and decisions, thoughts, speech, logic, problem-solving and memory storage (Earl, 2014). Related to this perspective is the contested idea that conscious human perception has limited bandwidth.
Two paradigms demonstrate this is change blindness (i.e. the inability to detect changes after a visual disruption or gradual change, Simons et al., 2000) and inattentional blindness (i.e. failure to perceive visible stimulus when attention is focused elsewhere). The latter paradigm was famously demonstrated in an experiment in which participants failed to notice a man in a gorilla costume when attention was directed on people passing a basketball (Simons and Chabris, 1999).
The two phenomena exemplify the bidirectional attention-perception influence interaction; perception is influenced by an absence of focused attention (i.e. change blindness) and by divided attention (i.e. inattentional blindness). An alternative explanation suggests that change is detected unconsciously but not consciously perceived. Spatial attention can be influenced without information entering conscious perception.
Jiang et al. (2006) featured suppressed and invisible pictures of nudes in a study which showed unconscious attention can be attracted, or repelled, by suppressed erotic images, relative to sexual orientation. This invites a different conclusion: we perceive more than we can attend to. One explanation comes from visual ensembles and summary statistics which suggests attended items are perceived at a higher resolution while peripheral stimuli are perceived in a low-fi ensemble (Cohen et al., 2016).
In auditory studies, intention and previous knowledge significantly influence perception. Techniques can manipulate and suppress auditory perception, which may allow researchers to precisely distinguish the different higher-level influences (Snyder et al., 2012). Overall, fundamental perception and attention questions remain unanswered, but progress continues.
Broadbent, D. E. (1958). Perception and communication. New York: Oxford University Press
Craighero, L., Nascimben, M., & Fadiga, L. (2004). Eye Position Affects Orienting of Visuospatial Attention. Current Biology, 14(4), p. 331-333. Doi:10.1016/j.cub.2004.01.054.
Craighero, L., Carta, A., & Fadiga, L. (2001). Peripheral oculomotor palsy affects orienting of visuospatial attention. Neuroreport, 12(15), 3283–3286. Doi:10.1097/00001756-200110290-00027
Cohen, M. A., Dennett, D. C., & Kanwisher, N. (2016). What is the Bandwidth of Perceptual Experience? Trends in Cognitive Sciences, 20(5). Doi:10.1016/j.tics.2016.03.006
Earl B. (2014). The biological function of consciousness. Frontiers in Psychology, 5, 697. Doi:10.3389/fpsyg.2014.00697
Jiang, Y., Costello, P., Fang, F., Huang, M., & He, S. (2006). A Gender- and Sexual Orientation-Dependent Spatial Attentional Effect of Invisible Images. Proceedings of the National Academy of Sciences of the United States of America, 103(45): 17048-52. Doi:10.1073/pnas.0605678103.
Koch, Christof & Tsuchiya, Naotsugu. (2007). Attention and Consciousness: Two Distinct Brain Processes. Trends in Cognitive Sciences, 11, 16-22. Doi:10.1016/j.tics.2006.10.012.
Mogg, K., & Bradley, B. P. (2002). Selective orienting of attention to masked threat faces in social anxiety. Behaviour Research and Therapy, 40(12), 1403–1414. Doi:10.1016/s0005-7967(02)00017-7
Pratt, J., & Taylor, E., & Gozli, D. (2015). Action and Attention. In J. M. Fawcett, E. F. Risko, & A. Kingstone (eds.), The Handbook of Attention. MIT Press
Rensink, R. (2009). Attention: Change Blindness and Inattentional Blindness. Encyclopedia of Consciousness, Vol. 1. Publisher: New York: Elsevier. (Ed. W. Banks). New York: Elsevier
Rizzolatti, G., Riggio, L., Dascola, I. & Umiltá, C. (1987). Reorienting attention across the horizontal and vertical meridians: evidence in favor of a premotor theory of attention. Neuropsychologia 25, 31–40. Doi:10.1016/0028-3932(87)90041-8.
Simons, D. J., Franconeri, S. L., & Reimer, R. L. (2000). Change blindness in the absence of a visual disruption. Perception, 29(10), 1143–1154. Doi:10.1068/p3104
Simons, D. J., & Chabris, C. F. (1999). Gorillas in Our Midst: Sustained Inattentional Blindness for Dynamic Events. Perception, 28(9), 1059–1074. Doi:10.1068/p281059
Smith, E. S., Fabian, P., Rosenthal, A., Kaddour-Djebbar, A., & Lee, H. J. (2015). The roles of central amygdala D1 and D2 receptors on attentional performance in a five-choice task. Behavioral Neuroscience, 129(5), 564–575. Doi:10.1037/bne0000077
Snyder., J, Gregg, M., Weintrau, D., & Claude, A. (2012). Attention, Awareness, and the Perception of Auditory Scenes. Frontiers in Psychology, 3. Doi:10.3389/fpsyg.2012.00015