In humans, information processing happens in stages, from raw sensory input down to a narrow conscious bottleneck:
In cognitive psychology: it’s a model of how the mind works — treating human thinking like a system that takes in information (through senses), encodes it, stores it (in short-term/working memory, then long-term memory), and retrieves it to guide behavior.
Sensory transduction
Physical stimuli (light, sound waves, pressure) get converted into electrical signals by receptor cells — photoreceptors in the eye, hair cells in the ear, etc.
This stage handles the massive bit rate (millions of bits/second).
Information processing is the set of operations that take raw data (or sensory input) and transform it into meaningful, usable information.
Key processes: attention, perception, encoding, rehearsal, retrieval, decision-making.
Human mind treated as a system that encodes, stores, retrieves, and manipulates information.
Classic stages: sensory memory → short-term/working memory → long-term memory.
Sensory memory Raw signals sit in a fleeting buffer for a few hundred milliseconds to a couple seconds — enough time for the brain to decide what’s worth keeping.
Selective attention-the filter.
The brain filters based on relevance, novelty, and salience — sudden movement, loud noises, and things related to current goals get through; everything else gets dropped: This is largely unconscious triage.
Cognitive processing speed — a core neuropsychological domain, often impaired in multiple sclerosis, traumatic brain injury, ADHD, depression, schizophrenia, and normal aging; commonly measured with the Symbol Digit Modalities Test or WAIS Processing Speed Index.
Working memory:short-term processing What survives attention gets held in an active, limited-capacity workspace where it can be manipulated, compared, or combined with existing knowledge.
Encoding into long-term memory
Information that’s rehearsed, emotionally significant, or connected to existing knowledge gets consolidated into long-term storage, often during sleep.
Retrieval and integration
Later, stored information gets reactivated and combined with new input to guide decisions and behavior.
The brain aggressively compress and discard information, keeping only what seems useful.
Conscious attention-Roughly 10–50 bits per second.
This is the rate at which people can consciously make decisions, read, or take in new information — surprisingly slow given how much data hits the senses.
Sensory intake-Senses take in something like 10 million to 1 billion bits per second, mostly through vision.
Almost all of this gets filtered out before it reaches conscious awareness.
Working memory: Classic estimate is “7 plus or minus 2” chunks of information, though more recent work suggests it’s closer to 3–4 chunks at a time.
Long-term memory: Storage capacity is enormous — estimates range into the terabytes over a lifetime, though retrieval is imperfect and reconstructive rather than exact.
Conscious processing is much slower than sensory intake.
Auditory processing disorder — difficulty interpreting auditory information despite normal hearing, relevant in pediatric and audiology settings.
Sensory processing — integration of sensory input, discussed in autism spectrum disorder and occupational therapy.
Modern views incorporate parallel distributed processing, embodied cognition, predictive processing, and neural network models rather than strict serial stages.
A general model of information processing: Input– receiving raw data or stimuli Encoding– converting it into a usable format Storage** – holding it (memory, in humans) Retrieval/Processing– accessing and manipulating the stored information Output-producing a response, decision, or result