Exploring The Possibilities Of Discovering The Neural Correlates Of Visual Consciousness

In the second phase of the experiment, the task and stimuli were the same, but following this phase, all of the subjects reported having seen the patterns. ERPs recorded over the occipital pole differed in amplitude from 220 to 260 msec for the pattern stimuli compared with the random arrays regardless of whether subjects were aware of the patterns. At subsequent latencies (300–340 msec) however, ERPs over bilateral occipital-parietal areas differed between patterns and random arrays only when subjects were aware of the patterns. Finally, in a third phase of the experiment, subjects viewed the same stimuli, but the task was altered so that the patterns became task relevant. Here, the same two difference components were evident but were followed by a series of additional components that were absent in the first two phases of the experiment. We hypothesize that the ERP difference at 220–260 msec reflects neural activity associated with automatic contour integration whereas the difference at 300–340 msec reflects visual awareness, both of which are dissociable from

The fascination with consciousness dates back to the time of Plato and Descartes. Since those times the term “consciousness” has spurned controversy in many scientific fields, including the fields of biology, psychology, and neuroscience. However, with the recent advancements in brain imaging technologies, such as functional magnetic resonance imaging (fMRI) and electroencephalography (EEG), human consciousness has shifted from being a subjective, abstract idea into being a observable scientific phenomenon. As neuroimaging capabilities progress, the public interest in consciousness also grows.

(1) The first question is dealing with the causal or functional role of phenomenal qualities: Under the assumption that seeing is based on cortical information-processing, the question arises, whether the phenomenal qualities of visual perceptions have a function with regard to this processing, in the sense that the intentional content of visual perceptions depends not only on their intentional, but also on their phenomenal qualities. Is it true, as among other authors Frank Jackson and Steven Pinker claim, that phenomenal qualities are only epiphenomena, not having any function for information-processing? (1)

Unit 8 Answer: Before answering this question, I will first define conscious awareness and neural circuit; conscious awareness is known as the “individual awareness of your unique thoughts, memories, feelings, sensations and environment” (Cherry, n.d.) while neural circuits are neural ensembles that process specific kinds of information such as visual or sensiorimotor input (Purves, 2001). As we have learned in previous chapters, neural mechanisms of conscious visual perception (the ventral stream) are not necessarily the same as those that mediate the visual control of behaviour (the dorsal stream). There are typically two hypotheses of how neural processing occurs consciously and unconsciously: response-chunking hypothesis and shifting control

The term ‘hallucination’ is difficult to define. There is a fine line between a ‘hallucination’ and an ‘illusion’. A hallucination differs from an illusion in that illusions are a product of misinterpretations of external stimuli whereas hallucinations need no such requirement making them an entirely internal process. A true hallucination can also be distinguished from a pseudo-hallucination in which the individual can recognise that what they’re seeing or hearing is not real. Hallucinations are also different from voluntary mental imagery, in that the thought has not uncontrollably forced itself onto our minds. Slade and Bentall (1988, cited in Blackmore, 2010)

Much is known about the way the cerebral cortex, the outer rind of the brain, initially analyses sensory messages. Yet investigations are only now beginning to suggest how the brain moves beyond the mere extraction of features-how it combines sensory messages with

Recently, empirical work within the predictive processing framework has started to question the role of consciousness in perceptual inference. Specifically, the idea that conscious awareness of sensory information is necessary to engage in predictive processing has been brought into question. Indeed, in the light of growing body of work demonstrating surprising functionality of unconscious neural activations, it can be asked (1) whether predictions can be formed based on regularities in the environment that we are not conscious of, (2) whether existing predictions be triggered not only by conscious, but also by unconscious cues, and (3) do we see neural signatures of prediction violation (i.e. prediction errors) in the case of an unconscious unexpected event? In this miniscriptie you will closely examine recent studies attempting to elucidate the relationship between consciousness and predictive processing by tackling these and other related

As expected, there is elevated activity in the primary visual cortex when presented with the stimuli. Furthermore, brain activity in the visual cortex is similar

Neurons are responsible primarily for their intended sense. However, neurons can sometimes be bimodal, meaning that they respond to two different senses. Primary sensory areas contain neurons that respond to only one sense. However, some primary sensory areas have outlier senses, and is not exclusive. Perception is defined as the brain’s interpretation of sensory information. However, that’s not all, since expectations also play a role in how the brain perceives the world. Therefore, it can be said that perception is a combination of sensory information and expectation. Helmholtz stated that previous experiences act in conjunction with present sensations to produce a perceptual image. Expectation dominates perception when there is

Figure 3 consists of five main parts including the SR, encoding, STM, WM, and LTM. In the following, each of them is briefly described. SR retains a quite accurate and the whole of the information, such as visual, auditory, tactile, taste, and olfactory, that is sensed and attended to. It is characterized by being outside of conscious control and occurs automatically. These steps include extracting and identifying the features of a stimulus after the initial reception of information regarding the stimulus. Here, thalamus is acted as a distributor of information, and all sensory information except the olfactory is passed through this part. In this level, attention

Pockett, S., Banks, W., & Gallagher, S. (2006). Does consciousness cause behavior? Cambridge, Mass.: MIT Press.

These activities demonstrate the attentional and perceptual deficiencies involved in a condition called blindsight. Blindsight is characterized by subconscious awareness, but perceptual blindness of stimuli in certain areas of the visual field. We consciously observe visual stimuli via the geniculocortical pathway, with structures including the lateral geniculate nucleus (LGN) in the thalamus and the primary visual cortex in the brain. This is the dominant visual pathway; however a smaller, evolutionarily older pathway exists and is still operational when the first pathway is damaged. The superior colliculus, a structure just below the LGN, receives information directly from the optic tract and thus creates a retinal map of its own. It passes

The function of subconscious mind is to store and retrieve data. Its job is to

The human brain receives input containing sensory information of different modalities from the surrounding environment. This information is processed in different areas of the brain that do not function in isolation and exhibit interactive plasticity (Roe et al., 1990). The processed information evokes activity in different cortical areas responsible for processing senses and is integrated to give coherent, detailed information (Molholm et al., 2002).

This shows that the pattern of a person's conscious experience or perception is structurally similar to the patterns of the activity of the brain. The isomorphism discussed in gestalt theory is mainly functional isomorphism. Behavior of a system as if it was physically similar in shape. It can only be assumed as the exact geometrical configuration of the brain but cannot be observed phenomenological.