Sensory Process-Auditory

Definition

Sensation – Sensing the external or internal stimuli.

Sensory Process - The process of detection of external or internal stimuli through the activation of sense organs (Eyes, ear, nose, skin and tongue).

Sensory Process

          Human activities results from the orders of brain which gets inputs from the various sense organs. The sense organs are activated by stimuli from the internal or external environment. The collective efforts of sensory organs, neurons, tissues, muscles, bones, brain and mind helps in receiving, organizing and finally interpreting the stimuli. The sensory receptors  (Specialized cells) of sense organs transform external or internal physical stimuli into electro-chemical signals known as neural impulse that travels via various channels to specific brain centres for further processing. This whole process of converting stimuli into neural impulse is known as sensory process.

Sensory Limits

          Sense organs too have certain limitations such as eye cannot see beyond visible spectrum of 380-780 nm, ears cannot hear beyond 20 Hz to 20000 Hz etc. A stimulus should have a minimum value to initiate sensation. The minimum value of a stimulus required to activate a given sensory system is known as ‘Absolute Threshold or Absolute Limen’ (NCERT).

          To differentiate between two stimuli there should be some minimum difference between the values of the two stimuli. The smallest  difference in the value of two stimuli that is  necessary to notice them as  different is called ‘Difference Threshold or Difference  Limen’ (NCERT). It is also  known as ‘Just Noticeable  Difference’ (JND).

Auditory Sensory Process

          Sound (speed is 343 m per sec in dry air at 20º C or 1100 ft per sec) is the chief component that activates the Ear and its hearing organs which initiate the auditory sensation. The auditory sensation provides spatial information, orient an individual towards an object and helps in verbal communication. Sound is the physical stimulus produced by the vibration of air molecules. Sound to have three important psychological properties i.e. Pitch (Frequency or wavelength), Volume (Amplitude), Timbre (richness in the tone i.e. saturation or purity). 

(i)       Loudness or Volume (Amplitude) – It is determined by amplitude of sound wave. Larger the amplitude louder the sound. Measured in decibels (db).

(ii)      Pitch (Frequency or wavelength) – Highness or lowness of sound. Higher the frequency higher the pitch. The seven notes in Indian classical music represent gradual increase in pitch.

(iii)     Timbre (saturation or purity) – The richness in the tone of sound or nature or quality of sound. It reflects the complexity of sound waves.

Reference:

1.       NCERT, XI Psychology Text book.

2.       Ciccarelli, S. K. & Meyer, G. E. (2016). Psychology. Noida: Pearson India.

3.       Baron, R. (1993).  Psychology.

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