Benefit finding among family caregivers of patients with advanced cancer in a palliative treatment: a qualitative study.

BACKGROUND: Benefit finding is the search for positive meaning from traumatic events, such as cancer. It can help caregivers have a positive experience in the caregiving process, relieve negative emotions, and reduce caregiving stress. The aim of this study was to explore benefit finding among caregivers of patients with advanced cancer in their palliative caregiving journey. METHODS: An exploratory qualitative design of phenomenology was used. Semistructured interviews were conducted with 19 caregivers of palliative care patients with advanced cancer. The Colaizzi 7-step analysis was used to analyse, summarize, and extract themes from the interview data. RESULTS: The study identified five themes of caregiver benefit finding in the caregiving process: personal growth, strengthened relationships with patients, adjustment and adaptation, perceived social support, and perceived meaning in life. Most caregivers reported a closer, more dependent relationship with the patient, and only one caregiver did not report any positive changes. CONCLUSIONS: Caregivers of palliative care patients with advanced cancer can have positive experiences in their care. Healthcare professionals should focus on supporting caregivers and helping them find positive experiences to cope with the challenges of caregiving and improve their quality of life.

Roles of the medial prefrontal cortex, mediodorsal thalamus, and their combined circuit for performance of the odor span task in rats: analysis of memory capacity and foraging behavior.

Working memory (WM), the capacity for short-term storage of small quantities of information for immediate use, is thought to depend on activity within the prefrontal cortex. Recent evidence indicates that the prefrontal neuronal activity supporting WM is driven by thalamocortical connections arising in mediodorsal thalamus (mdThal). However, the role of these connections has not been studied using olfactory stimuli leaving open the question of whether this circuit extends to all sensory modalities. Additionally, manipulations of the mdThal in olfactory memory tasks have yielded mixed results. In the present experiment, we investigated the role of connections between the rat medial prefrontal cortex (mPFC) and mdThal in the odor span task (OST) using a pharmacological contralateral disconnection technique. Inactivation of either the mPFC or mdThal alone both significantly impaired memory performance in the OST, replicating previous findings with the mPFC and confirming that the mdThal plays an essential role in intact OST performance. Contralateral disconnection of the two structures impaired OST performance in support of the idea that the OST relies on mPFC-mdThal connections, but ipsilateral control infusions also impaired performance, complicating this interpretation. We also performed a detailed analysis of rats' errors and foraging behavior and found a dissociation between mPFC and mdThal inactivation conditions. Inactivation of the mdThal and mPFC caused a significant reduction in the number of approaches rats made per odor, whereas only mdThal inactivation or mPFC-mdThal disconnection caused significant increases in choice latency. Our results confirm that the mdThal is necessary for performance of the OST and that it may critically interact with the mPFC to mediate OST performance. Additionally, we have provided evidence that the mPFC and mdThal play dissociable roles in mediating foraging behavior.

Task phase-specific involvement of the rat posterior parietal cortex in performance of the TUNL task.

The posterior parietal cortex (PPC) participates in cognitive processes including working memory (WM), sensory evidence accumulation, and perceptually guided decision making. However, surprisingly little work has used temporally precise manipulations to dissect its role in different epochs of behavior taking place over short timespans, such as WM tasks. As a result, a consistent view of the temporally precise role of the PPC in these processes has not been described. In the present study, we investigated the temporally specific role of the PPC in the Trial-Unique, Nonmatching-to-Location (TUNL) task, a touchscreen-based, visuospatial WM task that relies on the PPC. To disrupt PPC activity in a temporally precise manner, we applied mild intracranial electrical stimulation (ICES). We found that intra-PPC ICES (100 µA) significantly impaired accuracy in TUNL without significantly altering response latency. Moreover, we found that the impairment was specific to ICES applied during the delay and test phases of TUNL. Consistent with previous reports showing delay- and choice-specific neuronal activity in the PPC, the results provide evidence that the rat PPC is required for maintaining memory representations of stimuli over a delay period as well as for making successful comparisons and choices between test stimuli. In contrast, the PPC appears not to be critical for initial encoding of sample stimuli. This pattern of results may indicate that early encoding of visual stimuli is independent of the PPC or that the PPC becomes engaged only when visual stimuli are spatially complex or involve memory or decision making.

NMDA Receptors in Visual and Olfactory Sensory Integration in Male Long Evans Rats: A Role for the Orbitofrontal Cortex.

Sensory integration (SI) is a cognitive process whereby the brain uses unimodal or multimodal sensory features to create a comprehensive representation of the environment. Integration of sensory input is necessary to achieve a coherent perception of the environment, and to subsequently plan and coordinate action. The neural mechanisms mediating SI are poorly understood; however, recent studies suggest that the regulation of SI involves N-methyl-d-aspartate receptors (NMDARs) in orbitofrontal cortex (OFC). Thus, we tested this hypothesis directly in two experiments using object oddity tests that require SI for visual and olfactory stimuli. First, we blocked NMDARs with acute CPP treatment (i.p., 10 mg/kg) and tested rats in unimodal visual and olfactory SI tests, and respective control unimodal oddity tests that do not require SI. Second, we used intra-OFC infusions of AP5 (30 mM) to examine the role of NMDARs in the OFC in the oddity tests requiring SI. Systemic blockade of NMDARs impaired performance on the visual tests regardless of whether SI was required for determining oddity. In the olfactory tests, systemic treatment with CPP impaired the test requiring SI while sparing olfactory oddity, demonstrating a selective impairment in the olfactory SI. Intra-OFC blockade of NMDARs impaired olfactory SI, without effect on visual SI, demonstrating that intra-OFC NMDARs are essential for olfactory, but not visual SI. The present results are discussed in the context of the function of the OFC and its associated circuitry.