Since the time of Freud, the body has been ascendant in cognitive science, the
mind hidden and apparently described by neuron-to-neuron chemical connections
in the central nervous system. The last half of the 20th century presented
challenges to scientific understanding and logic that would force a profound
change in the older sciences. Mathematics, astronomy, physics, chemistry, genetics,
and cellular biology, scientific fields once characterized by simple formulas
reflecting concrete fact, transformed into complex interrelated spheres of activity
now defined by algorithms of possibility. In contrast, cognitive neuroscience
developed in this era, a distinctly new and apparently unique area of science,
exemplifying simplicity. Brain activities became amenable to easy understanding
when modeled on sequential firing of neurons as modulated by neurochemical
transmitters at the synaptic junctions between cells. This simple model has been
extraordinarily productive, serving as the basis for medical approaches as diverse
as pharmacologically based psychiatry and neurosurgery.
Unfortunately, like most myths that simplicity disappears with closer examination.
Simple “truths” of cognitive science flounder. For instance, everyone knows
Toward a Cognitive Psychology of Science: Recent Research and Its Implications In the article written by Ryan Tweney, he is contemplating the idea of whether there is a cognitive significance to scientific thinking. Many different studies are mentioned to try and answer this contemplation. One study on discovering the complexity of the universe found that subjects did the best if they confirmed ...
(check the textbooks) that the rapid eye movement (REM) sleep we see occurring
every 90 minutes each night is dreaming – right?
Except that almost all research indicates the contrary. REM sleep does not equate
with dreaming. REM sleep occurs without dreaming and dreaming occurs without
REM sleep. The two cognitive states are doubly dissociable. There is little evidence
that an actual physiologic correlate for dreaming exists. Although the REM sleep we
see on our electrical recordings of the brain during sleep is a state in which dreaming
may occur, dreaming also occurs throughout the other stages of sleep.
Many neuroscientists have built their careers on simple neurotransmitter constructs
of CNS functioning. There is good evidence that the neurochemical acetylcholine
is an on–off switch for REM sleep, modulated by other neurochemicals
including norepinephrine and serotonin. This view has proved to be much too
simple even when limited to the electrophysiological process we call REMS rather
than it’s loosely defined correlate of “dreaming.” Each CNS neuron, all hundred
billion plus, are likely to utilize more than one neurotransmitter and secondary
signaling systems. The neurotransmitters of the CNS have a multiplicity of highly
site-specific roles that may result in net changes on behavioral states and cortical
arousal that directly contrasts with effects at the microscopic level. Multiple factors
and systems are involved, with no single chemical neurotransmitter identified
as necessary or sufficient for modulating sleep and wakefulness. The drugs that
induce disturbed dreaming and nightmares are not those that affect REM sleep.
Drugs that alter REM sleep often have no effects on dreaming. Despite claims to
the contrary, we have only a limited, incomplete, and often incorrect knowledge of
the neurochemistry of conscious states.
Much of our knowledge of brain functioning comes from pathologic studies
and CNS scanning. Positron emission tomography (PET) and other scanning technologies
have found areas of the brain that are consistently activated during REM
Dreams are a form of cognitive activity that occur during sleep. Like vivid memories and daytime fantasies, dreams involve visual images in the absence of external visual stimulation. Some dreams are so realistic and well organized that we feel as though they must be real -- that we simply cannot be dreaming this time. Dreaming has always been the subject of controversy. Egyptian papyrus documents ...
sleep. If REMS is dreaming, these are the areas of brain that result in dream.
However, REMS may or may not be dreaming, and there is no way for the investigator
to determine whether dreaming in actually occurring when these areas are
activated. Pathologic brain damage can affect dream recall. Extensive basal-frontal
and parietal damage to the brain can produce a lack of dreaming. There are individuals,
however, without a history of brain damage that function normally without
ever recalling dreams. Do these individuals actually not dream? Such findings
have called into question whether neuropathology and CNS scanning provide
any clear evidence to support a brain-based site of origin for dreams.
There are, of course, clear brain based correlates for many areas of cognition.
Neuroscientists and clinicians understand the cognitive processes involved in perception
and motor activity quite well. We can create artificial constructs of these
systems that have more capabilities than biological systems. We are slowly discovering
the brain-based sites involved in other areas of cognitive processing.
The experience of dreaming includes visual imagery, emotions, and memories.
Since dreaming likely utilizes the same neuro-processing systems used for these
processes in waking, these components of dream are likely to have clear brainbased
There are other types of cognitive processing for which there is no clear associated
or specific brain activity. Most of these processes are cognitively described
as “thinking.” When awake, we think. We even think when we are asleep. Dream
thought describes the personal presence of the dreamer in the dream. The particular
type of associative thought that frames the imagery, emotion, and memory
of dreaming is also characteristic of the process of creativity – a process that often
What Are The Underlying Assumptions In Neuropsychology? Cognitive Neuropsychology (CN) studies and uses the relationship between normal and abnormal cognitive functioning to attain the following goals. 1. Using models of normal functioning to understanding impaired functioning. 2. Using knowledge of impaired and preserved cognitive abilities of brain-damaged patients to improve models of normal ...
incorporates dreams. Associative thought is the framework for imaginative construction,
the process through which the perceptually limited and thin images of
dream and waking imagery can produce the powerful and sometimes significant
experiences of dream that are capable of parodying or surpassing waking perceptually
The neurobiology of the human CNS is one of the most complex systems ever
studied making it tempting to reduce this system into simple constructs. Yet, theories
of cognitive function where simple physiological events represent complex
cognitive states such as dreaming have outlived their usefulness. Theories are
useful if they can be adapted or altered to fit new data. Theories can be harmful
if used to misrepresent the extent of knowledge or to limit the breath of study.
We find ourselves in an interesting position. Evidence is lacking to support a simple
brain equals mind paradigm. Yet, this Monist requirement lies at the basis of
current neuroscientific and psychoanalytic theories of mind.
Whether you look from outside/in as a cognitive scientist or from inside/out as
a human trying to understand, you are faced with the same unexplainable conundrum.
Just where is your mind?