Perception

Perceptual issues in philosophy include the extent to which sensory qualities such as sound, smell or color exist in objective reality rather than in the mind of the perceiver.

[4] The perceptual systems of the brain enable individuals to see the world around them as stable, even though the sensory information is typically incomplete and rapidly varying.

It involves a combination of somatosensory perception of patterns on the skin surface (e.g., edges, curvature, and texture) and proprioception of hand position and conformation.

These molecules diffuse through a thick layer of mucus; come into contact with one of thousands of cilia that are projected from sensory neurons; and are then absorbed into a receptor (one of 347 or so).

)[citation needed] The somatosensory cortex is a part of the brain that receives and encodes sensory information from receptors of the entire body.

[51] In particular, stimulation at 30–40 Hz led to animals looking at a familiar image for longer periods, as they would for an unfamiliar one, though it did not lead to the same exploration behavior normally associated with novelty.

There is also evidence that the brain in some ways operates on a slight "delay" in order to allow nerve impulses from distant parts of the body to be integrated into simultaneous signals.

Afferent sensory signals continuously interact with higher order cognitive representations of goals, history, and environment, shaping emotional experience and motivating regulatory behavior.

[63] The perceptual systems of the brain achieve perceptual constancy in a variety of ways, each specialized for the kind of information being processed,[65] with phonemic restoration as a notable example from hearing.The principles of grouping (or Gestalt laws of grouping) are a set of principles in psychology, first proposed by Gestalt psychologists, to explain how humans naturally perceive objects with patterns and objects.

The perceptual ecology approach was introduced by professor James J. Gibson, who rejected the assumption of a poverty of stimulus and the idea that perception is based upon sensations.

Gibson works from the assumption that singular entities, which he calls invariants, already exist in the real world and that all that the perception process does is home in upon them.

The constructivist view, held by such philosophers as Ernst von Glasersfeld, regards the continual adjustment of perception and action to the external input as precisely what constitutes the "entity," which is therefore far from being invariant.

[81] Glasersfeld considers an invariant as a target to be homed in upon, and a pragmatic necessity to allow an initial measure of understanding to be established prior to the updating that a statement aims to achieve.

[83] Evolutionary psychologists argue that animals ranging from fiddler crabs to humans use eyesight for collision avoidance, suggesting that vision is basically for directing action, not providing knowledge.

[88][89][90][91][92] The preattentive stage of perception is largely unconscious, and analyzes an object by breaking it down into its basic features, such as the specific color, geometric shape, motion, depth, individual lines, and many others.

[93] Cognitive psychologist professor Michael Tomasello hypothesized that social bonds between children and caregivers would gradually increase through the essential motive force of shared intentionality beginning from birth.

[94] The notion of shared intentionality, introduced by Michael Tomasello, was developed by later researchers, who tended to explain this collaborative interaction from different perspectives, e.g., psychophysiology,[95][96][97] and neurobiology.

Introduced by Latvian professor Igor Val Danilov, the hypothesis of neurobiological processes occurring during Shared intentionality[99] highlights that, at the beginning of cognition, very young organisms cannot distinguish relevant sensory stimuli independently.

Because the environment is the cacophony of stimuli (electromagnetic waves, chemical interactions, and pressure fluctuations), their sensation is too limited by the noise to solve the cue problem.

Research has focused on the relation of this to other kinds of learning, and whether it takes place in peripheral sensory systems or in the brain's processing of sense information.

[102] Empirical research show that specific practices (such as yoga, mindfulness, Tai Chi, meditation, Daoshi and other mind-body disciplines) can modify human perceptual modality.

Specifically, these practices enable perception skills to switch from the external (exteroceptive field) towards a higher ability to focus on internal signals (proprioception).

Increasing self-transcendence may enable yoga practitioners to optimize verticality judgment tasks by relying more on internal (vestibular and proprioceptive) signals coming from their own body, rather than on exteroceptive, visual cues.

[103] Past actions and events that transpire right before an encounter or any form of stimulation have a strong degree of influence on how sensory stimuli are processed and perceived.

For example, when engaging in conversation, we attempt to understand their message and words by not only paying attention to what we hear through our ears but also from the previous shapes we have seen our mouths make.

[62] They can be long term, such as a special sensitivity to hearing one's own name in a crowded room, or short-term, as in the ease with which hungry people notice the smell of food.

[107] In general, perceptual speed as a mental ability is positively correlated with personality traits such as conscientiousness, emotional stability, and agreeableness suggesting its evolutionary role in preserving homeostasis.

[110] Philosopher Andy Clark explains that perception, although it occurs quickly, is not simply a bottom-up process (where minute details are put together to form larger wholes).

[111] Indeed, predictive coding provides an account where this type of feedback assists in stabilizing our inference-making process about the physical world, such as with perceptual constancy examples.

Embodied cognition challenges the idea of perception as internal representations resulting from a passive reception of (incomplete) sensory inputs coming from the outside world.

The Necker cube and Rubin vase can be perceived in more than one way.
Humans are able to make a very good guess on the underlying 3D shape category/identity/geometry given a silhouette of that shape. Computer vision researchers have been able to build computational models for perception that exhibit a similar behavior and are capable of generating and reconstructing 3D shapes from single or multi-view depth maps or silhouettes. [ 1 ]
Cerebrum lobes
Anatomy of the human ear. (The length of the auditory canal is exaggerated in this image.)
Brown is outer ear .
Red is middle ear .
Purple is inner ear .
Though the phrase "I owe you" can be heard as three distinct words, a spectrogram reveals no clear boundaries.
Law of Closure. The human brain tends to perceive complete shapes even if those forms are incomplete.