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== Sensation ==

== Sensation ==

Sense organs are the primary sources for gathering information from the world around us and providing it to the mind for further processing. Sense organs receive the reflection emanating from the objects which are then reflected in the inner mind.

Sense organs are the primary sources for gathering information from the world around us and providing it to the mind for further processing. Sense organs receive the reflection emanating from the objects which are then reflected in the inner mind. A stimulus is a detectable input from the environment. 

Sensory receptors are specialized neurons that respond to specific types of stimuli. When sensory information is detected by a sensory receptor, sensation has occurred. For example, light that enters the eye causes chemical changes in cells that line the back of the eye. These cells relay messages, in the form of action potentials to the central nervous system. The conversion from sensory stimulus energy to action potential is known as transduction.<ref name=":0" />

Sensory receptors are specialized neurons that respond to specific types of stimuli. When sensory information is detected by a sensory receptor, sensation has occurred. For example, light that enters the eye causes chemical changes in cells that line the back of the eye. These cells relay messages, in the form of action potentials to the central nervous system.<ref name=":0" />

 

 

 

 

 

# '''Reception''': The process of receiving information in the form of light, heat or other physical energy by the sense organs having specialized sensory receptor cells is called reception. The minimum amount of physical energy needed to produce a sensory experience in a receptor cell is called '<nowiki/>'''absolute threshold'''.' For example, the tick of a watch six meters or twenty feet away can be heard under quiet conditions. A message below that threshold is said to be '<nowiki/>'''subliminal'''<nowiki/>'; such a message is processed but a person is not consciously aware of it. The minimum difference that a person can detect between two stimuli 50% of the time is termed as ''''just noticeable''' '''difference threshold'''<nowiki/>'. Examples include the noticeable difference in the pressure on the arm, and differences in the volume of music.

# '''Transduction''': The conversion of received physical energy or sensory stimulus energy into electric impulse or action potential is known as transduction. The electric impulses are the 'readable' forms of sensory information.

# '''Transmission''': The electric impulses travel from the source sensory organ to the brain for interpretation via the nerve fibers.

 

== Definition of Perception ==

== Definition of Perception ==

An awareness about the external stimuli gathered by the sense-organs is the result of a higher mental process called 'perception'. It helps us interpret the world around us and in making an appropriate decision in simple and complex situations and stimuli. Perception is a process of selecting, organizing, and interpreting the sensory information based on previous experiences, other's experiences, needs or expectations.

An awareness about the external stimuli gathered by the sense-organs is the result of a higher mental process called 'perception'. It helps us interpret the world around us and in making an appropriate decision in simple and complex situations and stimuli. Perception is a process of selecting, organizing, and interpreting the sensory information based on previous experiences, other's experiences, needs or expectations.

== Stages of Perception ==

== Process of Perception ==

Broadly, the process of perception involves three steps, when a stimulus is encountered.

Broadly, the process of perception involves three steps, when a stimulus is encountered.

=== 1. Selection ===

=== 1. Selection ===

Selection is the first stage of perception. At a given time, due to various factors, the human brain consciously or unconsciously, processes only some stimuli ignoring the others. For example, when engaged in deep conversation we tune out of many sounds in the background and do not register them. The selected stimulus becomes the "attended stimulus."<ref name=":1" /> It is well known that the five major senses are vision, hearing (audition), smell (olfaction), taste (gustation), and touch (somatosensation). We also have sensory systems that provide information about 

Selection is the first stage of perception. At a given time, due to various factors, the human brain consciously or unconsciously, processes only some stimuli ignoring the others. For example, when engaged in deep conversation we tune out of many sounds in the background and do not register them. The selected stimulus becomes the "attended stimulus."<ref name=":1" />  

Subsequent to selecting the stimulus the interpretation depends on how the information is organized for processing. Selection is influenced by some factors like attention.

Subsequent to selecting the stimulus the interpretation depends on how the information is organized for processing. Selection is influenced by some factors like attention.

Although our perceptions are built from sensations, not all sensations result in perception. In fact, we often don’t perceive stimuli that remain relatively constant over prolonged periods of time. This is known as sensory adaptation.<ref name=":0" />

Although our perceptions are built from sensations, not all sensations result in perception. In fact, we often don’t perceive stimuli that remain relatively constant over prolonged periods of time. This is known as sensory adaptation.<ref name=":0" />

Imagine a person entering a classroom having an old analog clock. Upon first entering the room, he can hear the ticking of the clock; as he engages in conversation with classmates or listens to professor greet the class, he shall no longer be aware of the clock ticking. The clock continues to tick, and that stimulus continues to affect the sensory receptors of the person's auditory system even as time passes. The fact that he no longer perceives the sound demonstrates sensory adaptation and shows that while closely associated, sensation and perception are different.<ref name=":0" />

Imagine a person entering a classroom having an old analog clock. Upon first entering the room, he can hear the ticking of the clock; as he engages in conversation with classmates or listens to professor greet the class, he shall no longer be aware of the clock ticking. The clock continues to tick, and that stimulus continues to affect the sensory receptors of the person's auditory system even as time passes. The fact that he no longer perceives the sound demonstrates sensory adaptation and shows that while closely associated, sensation and perception are different.<ref name=":0" /> When exposed to a stimulus over a period of time there will be a diminished sensitivity to it. Constant and persistent exposure to a stimulus may make a person unresponsive to it. For example, the water in a hot tub is hot initially and after a certain period of time it no longer seems as hot. So is the case with band aid which cannot be senses after wearing it for a while.

=== Attention ===

=== Attention ===

Attention plays a significant role in determining what is sensed versus what is perceived. Imagine you are at a party full of music, chatter, and laughter. You get involved in an interesting conversation with a friend, and you tune out all the background noise. If someone interrupted you to ask what song had just finished playing, you would probably be unable to answer that question. Failure to notice something that is completely visible because of a lack of attention is called inattentional blindness.<ref name=":0" />

Attention plays a significant role in determining what is sensed versus what is perceived. Imagine a party full of music, chatter, and laughter. When one is absorbed in an interesting conversation with a friend, and he/she gets tuned out all the background chatter or conversations which can be termed as noise. On interruption the person would probably be unable to answer what song was just played. Failure to notice something that is completely visible because of a lack of attention is called inattentional blindness.<ref name=":0" />  

 

 

=== Motivation ===

=== Motivation ===

Motivation can also affect perception. Have you ever been expecting a really important phone call and, while taking a shower, you think you hear the phone ringing, only to discover that it is not? If so, then you have experienced how motivation to detect a meaningful stimulus can shift our ability to discriminate between a true sensory stimulus and background noise.<ref name=":0" />

Motivation can also affect perception. Have you ever been expecting a really important phone call and, while taking a shower, you think you hear the phone ringing, only to discover that it is not so. If so, then you have experienced how motivation to detect a meaningful stimulus can shift our ability to discriminate between a true sensory stimulus and background noise.<ref name=":0" />

=== Cultural influence ===

=== Cultural influence ===

The shared experiences of people within a given cultural context can have pronounced effects on perception. For example, Marshall Segall, Donald Campbell, and Melville Herskovits (1963) published the results of a multinational study in which they demonstrated that individuals from Western cultures were more prone to experience certain types of visual illusions than individuals from non-Western cultures, and vice versa.<ref name=":0" />

The shared experiences of people within a given cultural context can have pronounced effects on perception. For example, Marshall Segall, Donald Campbell, and Melville Herskovits (1963) published the results of a multinational study in which they demonstrated that individuals from Western cultures were more prone to experience certain types of visual illusions than individuals from non-Western cultures, and vice versa.<ref name=":0" />

One such illusion that Westerners were more likely to experience was the Müller-Lyer illusion (Figure 5.3): The lines appear to be different lengths, but they are actually the same length. These perceptual differences were consistent with differences in the types of environmental features experienced on a regular basis by people in a given cultural context. People in Western cultures, for example, have a perceptual context of buildings with straight lines, what Segall’s study called a carpentered world (Segall et al., 1966). In contrast, people from certain non-Western cultures with an uncarpentered view, such as the Zulu of South Africa, whose villages are made up of round huts arranged in circles, are less susceptible to this illusion (Segall et al., 1999).<ref name=":0" />

One such illusion that Westerners were more likely to experience was the Müller-Lyer illusion. The lines appear to be different lengths, but they are actually the same length. These perceptual differences were consistent with differences in the types of environmental features experienced on a regular basis by people in a given cultural context. People in Western cultures, for example, have a perceptual context of buildings with straight lines, what Segall’s study called a carpentered world (Segall et al., 1966). In contrast, people from certain non-Western cultures with an uncarpentered view, such as the Zulu of South Africa, whose villages are made up of round huts arranged in circles, are less susceptible to this illusion (Segall et al., 1999).<ref name=":0" />

=== Personality ===

=== Personality ===

== How is perception produced? ==

== How is perception produced? ==

Perception Vs Pratyaksha Pramana

== Perception Vs Pratyaksha Pramana ==

== References ==

== References ==

[[Category:Yoga]]

[[Category:Yoga]]

[[Category:Darshanas]]

[[Category:Darshanas]]