Five spiritual senses:

As Allah has created five physical senses for the material world so has He endowed human intellect with five spiritual senses? These are:

Common Sense
Imagination
Thinking
Memory
Association

Brief summary of each of these senses is given below.

Common Sense: No sooner this faculty of human intellect receives data from physical senses than they get absorbed into it. For instance, when our eyes see something, common sense takes and accepts this sensation. It can be illustrated with the similitude of a pond that is common sense and five physical senses are five drains bringing water into it.
Imagination: It preserves the shapes and images of sensations and perceptions received in the common sense pool from sensory channels. For example when we hear the word “Lord” its images “L, O, R, D” are stored in imagination.
Thinking: This spiritual sense perceives the meaning and implications or spiritual forms of physical sensual stimulations and transfers the received impressions to the next sense for preservation.
Memory: It retains meanings of sensations in the same way as imagination stores their physical images.
Association: It connects meaning preserved in faculty of thinking to the physical images saved in imagination. This enables us to understand and differentiate between words on hearing them. All these five senses work jointly and with mutual cooperation and coordination. It is here where sensory information changes into knowledge and understanding. These senses may break down if common sense is wiped out. Each sense has a link with the other. They are ineffective and unproductive without one another.

This syllogistic study clearly proves that physical five senses depend upon spiritual five senses to culminate into knowledge and understanding. The perceptions of material realities received through physical senses can mature into knowledge only if they develop into some conclusion through spiritual senses. Physical senses can only perceive a thing but cannot know it. On the other hand intellect and spiritual senses too are dependent upon physical senses. If all sense organs fail to perform their functions, intellect just cannot draw any conclusion owing to absence of the required data. So intellect and senses are interdependent.

Our senses are extremely susceptible to environmental impressions. If a newborn baby is shifted immediately after his birth to a place where there is no voice to stimulate his audition, he will grow abnormal, unable to speak or understand any word even after getting fifty years old. It will happen for the sole reason that whatever we say results from whatever we hear. That is the learning phenomenon. We hear voices, which our memory retains. The intellect supplies meanings to these voices through the process of association. Then we reproduce the same voices on the S.I.R. pattern: stimulation, integration and response. If there is no stimulant, there will be no response and no learning simultaneously. If a man does not hear anything his intellect will remain barren, unable to retain any voices, words, syllables, enunciations, accents, rhythms and styles. His mind remains like a clean slate with no impressions drawn on it. Likewise, he also cannot and does not acquire any capability to say and express his feelings, desires and needs. It was for the same reason that in the Holy Prophet’s times the Arabs used to send their children with rural women so that they might learn pure and fluent Arabic through hearing them, talking to them, getting corrected by them and by living with them.