Cognition ❮ 143of information. Baddeley’s working memory model is an active three-part memory system
that temporarily holds information and consists of a phonological loop, visuospatial working
memory, and the central executive. The phonological loop briefly stores information about
language sounds with an acoustic code from sensory memory and a rehearsal function that
lets us repeat words in the loop. Visuospatial working memory briefly stores visual and
spatial information from sensory memory, including imagery, or mental pictures. The
central executive actively integrates information from the phonological loop, visuospatial
working memory, and long-term memory as we associate old and new information, solve
problems, and perform other cognitive tasks. Working memory actively processes visual and
auditory information, and focuses our attention. Working memory accounts for our ability
to carry on a conversation (using the phonological loop), while exercising (using visuo-
spatial working memory) at the same time. Most of the information transferred into long-
term memory seems to be semantically encoded.
Long-Term Memory
Long-term memory is the relatively permanent and practically unlimited capacity memory
system into which information from short-term memory may pass. LTM is subdivided
into explicit memory and implicit memory. Explicit memory, also called declarative
memory, is our LTM of facts and experiences we consciously know and can verbalize.
Explicit memory is further divided into semantic memory of facts and general knowledge,
and episodic memory of personally experienced events. Implicit memory, also called
non-declarative memory, is our long-term memory for skills and procedures to do things
affected by previous experience without that experience being consciously recalled. Implicit
memory is further divided into procedural memory of motor and cognitive skills, and
classical and operant conditioning effects, such as automatic associations between stimuli.
Procedural memories are tasks that we perform automatically without thinking, such as
tying our shoelaces or swimming.
Organization of Memories
How is information in long-term memory organized? Four major models account for
orga ni za tion of LTM: hierarchies, semantic networks, schemas, and connectionist networks.
Hierarchies are systems in which concepts are arranged from more general to more specific
classes. Concepts, mental representations of related things, may represent physical objects,
events, organisms, attributes, or even abstractions. Concepts can be simple or complex.
Many concepts have prototypes, which are the most typical examples of the concept. For
example, a robin is a prototype for the concept bird; but penguin, emu, and ostrich are not.
The basic level in the hierarchy, such as bird in our example, gives us as much detail as we
normally need. Superordinate concepts include clusters of basic concepts, such as the con-
cept vertebrates, which includes birds. Subordinate concepts are instances of basic concepts.
Semantic networks are more irregular and distorted systems than strict hierarchies, with
multiple links from one concept to others. Elements of semantic networks are not limited
to particular aspects of items. For example, in a semantic network, the concept of bird can
be linked to fly, feathers, wings, animals, vertebrate, robin, canary, and others, which can be
linked to many other concepts. We build mental maps that organize and connect concepts
to let us process complex experiences. Dr. Steve Kosslyn showed that we seem to scan a
visual image of a picture (mental map) in our mind when asked questions. Schemas are
preexisting mental frameworks that start as basic operations and then get more and more
complex as we gain additional information. These frameworks enable us to organize and
interpret new information, and can be easily expanded. These large knowledge structures
influence the way we encode, make inferences about, and recall information. A script is
a schema for an event. For example, because we have a script for elementary school,