This is my understanding of the background to the development of schizophrenia: its proximate Cause, it's Treatment, it's Care.
Schizophrenia comes about because of a brain change in those people developing the illness.
The hippocampus area of the brain, in their case, proliferates only half the new cells of what is it's normal achievement. [ normally 700 new cells daily: Spalding et al Spalding et al ] 'we found 1/3 cell population were normally subject to exchange ]
The consequence of this change is a failure to perform the process of selecting, distinguishing that which is useful to know, from what is perceived - the incoming stimuli/information - to be going on outside, the information that is salient experience, personally useful to go into longterm store, whilst being able to disregard what is already known, not having to go over it all again. How and where would the brain deal with this surplus stimuli/information, pointless information that has some how 'got in'.
Without the ongoing update of useful information.
People with schizophrenia are at a disadvantage, when coping with day to day expectations requiring decision making, especially completing sequences in decisions that require a holding in mind of an awareness of the changing context behind those decisions.
A good example comes in conversation, when the longer it goes on, the more likelihood there is of veering off the subject, forgetting the context, led from the beginning, so that there are intrusions of idiosyncratic words and associations,to an eventual peetering out.
Another drawback following hippocampal neurogenesis reduction is the inability to 'rehearse in mind' what will be done in the future, the near and soon future. That is 'Prospective memory
The hippocampus is integrating or binding to-gether different aspects of a memory at the time of recollection.
[ The thalamus is the coordinator of long-term memory consolidation, the process where recently acquired information is transferred from the hippocampus to the cortex to be filed away as long-term memory. The hippocampus is like a hub, where a lot of information comes in and has to be redirected to the correct destination within the brain, especially to the cortex. This study shows that the thalamus seems to mediate the information exchange between hippocampus and cortex. "We think that memorization during deep sleep has to do with time coordination. If the hippocampus tries to exchange information when the cortex neurons are not ready to receive it, the information could be wasted," describes Latchoumane. "Slow oscillations might be the signal used by the cortex to flag that it is ready to accept information. Then, the thalamus would alert the hippocampus via the spindles." ]
Hippocampal new cells encode information stimuli temporarily, for eventual brain storage. They also retrieve such information , again temporarily, whilst being used to provide the changing context, as working memory proceeds, sometimes supporting prospective memory.
In schizophrenia when the hippocampus fails to proliferates enough new cells, the hippocampus connections cannot cope with sorting out of all the stimuli/information coming in.
It is likely to be overloaded with incoming stimuli.
How and where would the brain deal with this surplus stimuli/information, pointless information that has some how 'got in'?
[ This is what happens to people without schizophrenia during overload in 'normal' situations .
Fuerte et al 2006: distraction ]
Those with schizophrenia will experience information overload in normal circumstances; especially when anxious, or made anxious.
This is what happens during overload distraction in normal people.
Fuerte et al 2006: distraction
What is going on in overload is by- passing the selecting process of the hippocampus, ending up instead in the basal ganglia mid-brain striatal memorising stream.
The striatum/putamen stream is where incoming stimuli carrying information are given significance [ hey! cortex - this has to get attention ... serotonin receptors] and is given emotional priority [ deal with this, please: striatal dopamine ] then off to the cortex that receives, and deals with storage of relevant experience, where it then requires an explanation, a stabilising coherent account of 'why' this abnormal incoming stimuli has got in to the striatal route, requiring some 'sense'of dealing with it, leading to the delusional story.
The brain needs a narrative explanation [ see Gazzaniga :- studying 'split'brains
Gazzaniga describes - " the amazing capacities of the non-speaking right cerebral hemisphere, and the wild confabulations of the speaking left hemisphere when asked to explain actions and decisions of its disconnected partner"
Gazzaniga found that if the right brain was given an ambiguous set of perceptions - or a situation so opposite that it was difficult to make it coherent, found that the left brain always made a solution that put sense into the conflicting positions ]
abnormal salience especially when distractors are present
Hence forward, sufferers have to live in two somewhat different worlds: reality, and the variably intrusive influence of the delusional account.
How is it that sufferers do not argue against the delusional story? I think this comes from 'the story' having been developed through the striatal memory route, and consolidated like a procedural experience .
That route is for routinised repetition behaviour, belief that has become habituated , automated , less open to flexibility. Suitable for enduring stability, as in learning a skill, such as riding a bicycle or relying on a basic structure of grammar. They don't have to be learnt again and again.
In schizophrenia, with a much reduced hippocampus new cell prioliferation, 'consolidation' of this overload of stimuli/information coming to the rest of the brain via this striatal route might be less open to reflection, less open to what the brain with normal hippocampal neurogenesis can do using 'second thoughts': so that a delusional narrative is made, can persist, uncorrected.
One explanation might be that it is consolidated during Rem sleep where laft over emotional stuff is dealt with: 'overflow' from earlier nights sleep review of unusual information is dealt with.
Why do people with shizophrenia hear 'voices'.
My explanation is that this is what happens, in many normal people during 'brain idling' or 'mind wandering': there will be people heard 'talking'
- in schizophrenia people this kind of 'mind wandering' for the sufferers, comes out of the delusional narrative, the delusional explanation, created 'outside' the way 'the brain' exercises 'it's' usual internal checking scrutiny system. ?
I also think the delusion comes similarly from 'mind wandering' during which 'the brain' seeks a narrative that is prepared to address fear difficulties Perhaps from a process of consolidating during REM sleep, that seems to be where emotional concerns are dealt with. ?.
It is often critical , commenting adversely, threatening, intrusive and commanding.
How is it that all medications that help and prevent relapse are dopamine blockers? [ 'dopamine's role is by influencing the priority of such
stimuli for the person concerned'. It also takes part in giving memories their longterm 'status'.
] It is dopamine that establishes the emotional value - fear or joy - in this case registers the continual anxiety when reduced hippocampal neurogenesis makes the stimuli recognition world an uncertain place for the sufferer.
Clinically it is unresolved anxiety that leads to relapse, particularly if it comes out of troubled support from carers, family and professionals.
Bear in mind that a basic, continuing, fault in schizophrenia is how and what to hold 'on standby, when and where to use it with what is going to come up in the day and the week;what to carry along in 'stand by' memory, what else there is going on in any transaction.
New cell production in the hippocampus does that job normally.
With reduced neurogenesis, now they do not produce enough.
They are stuck with skills, interests and stored experience that they held before the age when the illness started: those with some continuing schizophrenia , have to try and make do with less new cells , less quick 'stand by' context. They do not 'move on' from the age when the illness presents
Socially, give more time, especially have more patience: less hurried interruption is required
Keep in touch with their lives, in a way that lets you intervene for the patient's best interests. [ see ... page 2 ]
'Best Interests' rules legally. It is what gives you authority in caring, on equal terms with the professional Teams. Often you know patient better. Their limited capability.
To respond on the patients behalf to the professional 'mantra' .. 'it's their choice' they are adults...we can't intervene. Professional staff that have their own best interests as their lead, 'it was their choice' - we have to respect choice .. as well, 'we have to gain their trust'.
Choice to do something that is against their best interest