To save content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about saving content to .
To save content items to your Kindle, first ensure email@example.com
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
This chapter illustrates the complexity of personality by the exploration of its neurobiology, including neurochemistry, and neuroanatomy via the temperament and character dimensional model and its relationship to psychiatric and neurological disorders. Thomas and Chess conceptualized temperament as the stylistic component of behavior, as differentiated from the motivation and content of behavior. Character is influenced by socio-cultural learning and matures in progressive steps throughout life. Character can be measured in three dimensions: self-directedness, cooperativeness, and self-transcendence. Personality dimensions involve complex adaptive systems of multiple genetic and environmental variables. Both gene-gene and gene-environment interactions are expected for understanding quantitative developmental phenomena and these have been abundantly confirmed for personality. Gene-environment interaction has also been demonstrated for novelty seeking and for harm avoidance in prospective population-based studies. Twin studies show that human personality traits are roughly equally influenced by genetic and by environmental influences.
That learning and memory deficits persist many years following mild traumatic brain injury (mTBI) is controversial due to inconsistent objective evidence supporting subjective complaints. Our prior work demonstrated significant reductions in performance on the initial trial of a verbal learning task and overall slower rate of learning in well-motivated mTBI participants relative to demographically matched controls. In our previous work, we speculated that differences in strategy use could explain the differences in rate of learning. The current study serves to test this hypothesis by examining strategy use on the California Verbal Learning Test-Second Edition. Our present findings support the primary hypothesis that mTBI participants under-utilize semantic clustering strategies during list-learning relative to control participants. Despite achieving comparable total learning scores, we posit that the persisting learning and memory difficulties reported by some mTBI patients may be related to reduced usage of efficient internally driven strategies that facilitate learning. Given that strategy training has demonstrated improvements in learning and memory in educational and occupational settings, we offer that these findings have translational value in offering an additional approach in remediation of learning and memory complaints reported by some following mTBI. (JINS, 2011, 17, 709–719)
Following mild traumatic brain injury (TBI), a percentage of individuals report chronic memory and attention difficulties. Traditional neuropsychological assessments often fail to find evidence for such complaints. We hypothesized that mild TBI patients may, in fact, experience subtle cognitive deficits that reflect diminished initial acquisition that can be explained by changes in cerebral white matter microstructure. In the data presented here, a sample of nonlitigating and gainfully employed mild TBI patients demonstrated statistically significant differences from age and education matched control participants in performance on the first trial of a verbal learning task. Performance on this trial was associated with reduced fractional anisotropy in the uncinate fasciculus and the superior longitudinal fasciculus providing an anatomical correlate for the cognitive findings. Mild TBI patients were not impaired relative to control participants on total learning or memory composite variables. Performance on the first learning trial was not related to any psychological variables including mood. We concluded that patients with mild TBI demonstrate diminished verbal learning that is not often interpreted in standard neuropsychological assessment. (JINS, 2010, 16, 506–516.)
Previous studies of rod photoreceptors in vivo have employed
a paired-flash electroretinographic (ERG) technique to determine rod
response properties. To test whether absence versus presence of
the ERG b-wave affects the photoreceptor response derived by the
paired-flash method, we examined paired-flash-derived responses obtained
from nob mice, a mutant strain with a defect in signal
transduction between photoreceptors and ON bipolar cells that causes a
lack of the b-wave. Normal littermates of the nob mice
served as controls. The normalized amplitude-intensity relation of the
derived response determined in nob mice at the near-peak time of
86 ms was similar to that determined for the controls. The full time
course of the derived rod response was obtained for test flash strengths
ranging from 0.11 to 17.38 scotopic cd s m−2 (sc cd s
m−2). Time-course data obtained from nob and
control mice exhibited significant but generally modest differences. With
saturating test flash strengths, half-recovery times for the derived
response of nobversus control mice differed by ∼60
ms or less about the combined (nob and control) average
respective values. Time course data also were obtained before
versus after intravitreal injection of
l-2-amino-4-phosphonobutyrate (APB) (which blocks transmission
from photoreceptors to depolarizing bipolar cells) and of cis
2,3-piperidine dicarboxylic acid (PDA) (which blocks transmission to OFF
bipolar cells, and to horizontal, amacrine and ganglion cells). Neither
APB nor PDA substantially affected derived responses obtained from
nob or control mice. The results provide quantitative information
on the effect of b-wave removal on the paired-flash-derived
response in mouse. They argue against a substantial skewing effect of the
b-wave on the paired-flash-derived response obtained in normal
mice and are consistent with the notion that, to good approximation, this
derived response represents the isolated flash response of the
photoreceptors in both nob and normal mice.
Traditional models of human memory have postulated the need for a brief phonological or verbatim representation of verbal input as a necessary gateway to a higher level conceptual representation of the input. Potter has argued that meaningful sentences may be encoded directly in a conceptual short-term memory (CSTM) running parallel in time to such a phonological store. The primary aim of the current study was to evaluate two main tenets of the CSTM model: that linguistic context biases selection of information entering the conceptual store, and that information not integrated into a coherent structure is rapidly forgotten. Results confirmed these predictions for spoken sentences heard by both young and older adults, supporting the generality of the model and suggesting that CSTM remains stable in normal aging.
A total of 130 young adults and 173 older adults gave goodness of fit ratings for sets of word alternatives for 123 English sentence frames. Word alternatives were semantically plausible in all cases but varied in the likelihood of their occurrence within the sentence frames. Adding support to the general belief that vocabulary and language knowledge are well preserved in normal aging, our results showed generally high agreement in goodness of fit ratings by the young and older adults. Differences that did occur appeared to be due to cohort differences in word usage and interests rather than underlying cognitive function. We suggest that this similarity in semantic judgments may help to explain why adult age differences in comprehension and memory for sentences are generally smaller than age differences for other examples of episodic memory.
Email your librarian or administrator to recommend adding this to your organisation's collection.